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Skin Asset Reference

The Skin asset type is the data definition for every cosmetic weapon skin, item reskin, and pattern texture in the Unturned™ economy. Skins allow items to have alternate visual appearances without changing their gameplay properties. The skin system supports primary materials for the item body, secondary materials for specific attachments, layered attachment materials, fallback attachment materials, and custom mesh overrides. The skin .dat format is distinct from the standard item .dat format and uses its own field set.

57 Studios™ has documented and validated the full skin asset configuration surface across the 74 base item categories that have skin support, encompassing over 520 skin folders and 64 pattern folders in Bundles\Skins\ and Bundles\Skins\Patterns\. This article covers every field that applies to skin assets, the pattern asset format for shared texture patterns, the four skin material types, the custom model override system, and the skin-to-item linkage mechanism.

A skin asset applied to an assault rifle in Unturned, showing the custom material replacing the default weapon texture

Documentation source: This article references the official Smartly Dressed Games modding documentation for field definitions and game behavior. Additional detail is drawn from the shipped skin .dat files in Bundles\Skins\ and the curated items guidelines in the Official SDG documentation.

Who this article is for

This article is written for Unturned™ mod authors who want to create custom skins for weapons and items, submit curated cosmetic items to the Steam Workshop stockpile, or understand the skin system for mod compatibility purposes. Artists creating texture replacement content should understand the four material types and how they map to different parts of the item model. Mod pack maintainers should understand the skin-to-item linkage mechanism to ensure skins appear on the correct base items.

How the skin system works

The skin system maps a visual override to a specific base item through an ID linkage. Each skin .dat file declares a numeric ID that matches the ID of the target base item. When the engine loads a skin asset, it applies the skin's materials and optional mesh overrides to the base item's model at runtime. The skin does not change any gameplay properties of the base item; it is purely a visual replacement.

As shown in the flowchart above, the skin system operates as a visual override layer on top of the base item's model. The ID linkage is the most critical field -- a skin with a mismatched ID does not appear on any item.

The four skin material types

Material typeFile patternPurpose
PrimarySkin_Primary.matThe main material used by the skinned item itself. Every skin should have a single primary material.
SecondarySkin_Secondary_#.matMaterial for a specific attachment (where # is the attachment's legacy ID). Skins can have multiple secondary materials.
Attachment (layered)Skin_Attachment.matUsed when a secondary material has not been provided for an attachment that has texture masks. For example, the 8x Scope has its mount and knobs masked out.
Tertiary (fallback)Skin_Tertiary.matUsed when none of the other included materials are applicable for an attached attachment. Usually identical to the layered attachments material.

The official SDG documentation notes that the Fiesta Augewehr skin includes all four types of materials. Most skins keep their layered and fallback textures identical, but this is not required. The Bloodsport Calling Card, Bouquet Bluntforce, and Vortex Augewehr are cited as good examples of skins with fairly different secondary, attachment, and tertiary materials.

The 74 base item categories with skin support

The shipped skin files cover 74 base item categories. Each category has its own subdirectory under Bundles\Skins\ and contains one or more skin variant folders. Major skin categories include:

Item categoryNumber of skinsNotable skins
Ace5+Accelerator, Fiesta, Inferno, Militia_Ace, Ornate
Augewehr3+Multiple variants
Cobra3+Multiple variants
Eaglefire3+Multiple variants
Maplestrike3+Multiple variants
Sabertooth3+Multiple variants
Canned_Beans2+Multiple variants
Detonator2+Multiple variants

The pattern skins under Bundles\Skins\Patterns\ provide an additional 64 shared texture sets that can be applied across multiple item categories through the Pattern flag.

Skin file structure

Standard skin (no custom mesh)

A skin without a custom mesh override does not include a prefab. The asset-bundled files include only the material files:

MySkin/
├── Skin_Primary.mat
├── Skin_Secondary_#.mat (one per attachment, optional)
├── Skin_Attachment.mat (optional)
└── Skin_Tertiary.mat (optional)

Custom mesh skin

A skin that overrides the item's original model includes prefab files for each LOD:

MyCustomMeshSkin/
├── Override_Mesh_0.prefab (LOD 0)
├── Override_Mesh_1.prefab (LOD 1, optional)
├── Skin_Primary.mat
├── Skin_Secondary_#.mat
└── ...

The Override_Mesh_#.prefab naming convention uses the LOD index as the number suffix. The prefab includes a Mesh Filter component linked to the custom model.

Complete .dat field reference

Identity fields

FieldTypeRequiredPurpose
GUIDuint128 hexYes128-bit globally unique identifier for the skin. Must be unique across all loaded assets.
TypestringYesMust be set to Skin for the parser to recognize this as a skin definition.
IDuint16YesThe numeric item ID of the base item this skin applies to. The skin appears on the item whose ID field matches this value.

Attachment slot assignment

FieldTypeRequiredPurpose
SightflagNoPresence indicates this skin provides a sight attachment material.
TacticalflagNoPresence indicates this skin provides a tactical attachment material.
GripflagNoPresence indicates this skin provides a grip attachment material.
BarrelflagNoPresence indicates this skin provides a barrel attachment material.
MagazineflagNoPresence indicates this skin provides a magazine attachment material.

Pattern field

FieldTypeRequiredPurpose
PatternflagNoPresence indicates this skin uses a pattern texture shared across multiple skins. The pattern texture is loaded from a Skin_Pattern subdirectory.

Skin .dat example (Ace Accelerator)

The shipped Ace Accelerator skin .dat file:

GUID 105f52557595497aa8a9666055c96832
Type Skin
ID 128

This minimal skin definition declares that the skin applies to item ID 128 (the Ace weapon), with no attachment slot flags set, and no pattern flag.

Pattern skin .dat example (Aces pattern)

The shipped Aces pattern .dat file:

GUID 9cc4868cbb2f45e6a4343fa5c61930a3
Type Skin
ID 147

Sight
Tactical
Grip
Barrel
Magazine

Pattern

This pattern skin applies to item ID 147, provides material overrides for all five attachment slot types, and uses the Pattern flag to indicate it references a shared pattern texture.

Pattern assets

Pattern assets are a subtype of the skin system that allows multiple skins to share a common texture pattern. The pattern texture is stored in the Skins\Patterns\<PatternName>\ folder alongside a .dat file that references the pattern's target item ID. The 64 shipped patterns include texture sets at different resolutions (Arctic_1024x1024, Arctic_512x512, etc.).

Creating a skin

Step 1: Create the albedo texture

At minimum, create a custom albedo texture for the skin. You can also add custom metallic or emission textures. Follow the curated item guidelines for resolution: 2048x2048 scaled down to 1024x1024 for large items, 1024x1024 scaled down to 512x512 for small items.

Step 2: Create the material files

Set up the material files in your Unity project. The primary material (Skin_Primary.mat) is required. Secondary, attachment, and tertiary materials are optional but recommended for full attachment coverage.

Step 3: Author the .dat file

GUID <generated-uuid-no-hyphens>
Type Skin
ID <target-item-id>

Add the attachment slot flags if the skin provides materials for those attachment types. Add the Pattern flag if using a shared pattern.

Step 4: Package and export

Include the material files (and optional mesh overrides) in the asset bundle. If submitting for curated status, export a Unity package following the curated items workflow.

Step 5: Test in-game

Spawn the base item and verify the skin appears correctly. Test with each attachment type that the skin supports.

Skin submission guidelines

The SDG curated items guidelines include specific requirements for skin submissions:

GuidelineDetail
Resolution2048x2048 scaled to 1024x1024 for large items; 1024x1024 scaled to 512x512 for small items
ContrastAvoid high contrast colors; do not go darker than #1e1e1e or brighter than #f0f0f0
EdgesClothing edges should have a slightly darker 1px border
CamouflageFlat ghillie-style blends are not allowed; patterned camouflage is acceptable
MetallicsUse metallic/smoothness values conservatively; Unturned does not use reflection probes
BevelsDo not bevel model corners; maintain the 90-degree sharp-edge art style
Custom modelsShould respect the original item's silhouette; attachments must still work and look good
ShadersCustom shaders are not supported; only vanilla shaders can be used
PhysicsPhysics cannot be used on cosmetics
CopyrightOnly submit content you created yourself; do not use copyrighted material

Diagnostic table

SymptomMost likely causeResolution
Skin does not appear on the target itemID field does not match the base item's IDVerify the skin's ID matches the target item's ID
Skin appears but with default materialsMaterial files not included in the bundleVerify Skin_Primary.mat is in the bundle
Skin appears but attachments show default texturesSecondary materials missing for those attachment IDsAdd Skin_Secondary_#.mat files for each attachment
Custom mesh not loadingOverride_Mesh_0.prefab missing or incorrectly namedVerify the prefab is named with the correct LOD index
Pattern skin uses wrong texturesPattern flag set but pattern texture not foundVerify the pattern folder structure matches the vanilla convention
Skin icon renders incorrectlyIcon measurement not configuredCheck item icon setup in the Unity prefab
Pink material on skinShader missing in the bundleRe-export with the correct shader inclusion
Skin works in single-player but not on serverServer does not have the skin's master bundleCopy the master bundle to the server's mod directory

Testing a skin asset in-game

Testing a skin asset requires verifying that the skin applies to the correct base item and that all material overrides work with the intended attachments.

Step 1: Verify the skin applies to the target item

Spawn the base item using the @give command with the base item's ID. Place the item on the ground or equip it. Confirm that the skin's textures are visible on the item model.

Step 2: Verify attachment coverage

Attach each type of supported attachment (sight, tactical, grip, barrel, magazine) to the skinned item. Confirm that each attachment displays the skin's secondary material (if provided) or falls back gracefully to the layered or fallback material.

Step 3: Verify custom mesh override (if applicable)

If the skin includes custom mesh overrides, confirm that each LOD level's override mesh loads correctly. Verify that attachments still snap to the correct positions on the custom mesh.

Step 4: Test with multiple copies

Spawn multiple copies of the skinned item and confirm that each copy displays the skin correctly. Verify that the skin persists across save-and-load cycles.

Step 5: Verify the skin icon

Confirm that the skin's icon in the inventory UI renders correctly. The icon should clearly represent the skin's appearance.

Skin design patterns

The full-coverage pattern

A skin that provides primary, secondary, layered, and fallback materials covers every possible attachment configuration. The Fiesta Augewehr is the canonical example. This pattern is recommended for Workshop submissions because it guarantees a consistent appearance regardless of which attachments the player uses.

The minimal pattern

A skin that only provides a primary material. Attachments use their default textures. This pattern is quick to produce but leaves attachment appearances inconsistent with the skin's visual theme. Appropriate for personal-use skins or early development iterations.

The custom mesh pattern

A skin that replaces the base item's model entirely. The official documentation recommends that custom mesh overrides still respect the original item's silhouette. The Bloodsport Calling Card and Vortex Augewehr demonstrate this pattern.

The shared pattern pattern

A skin that uses the Pattern flag to reference a shared texture pattern stored in the Patterns directory. Multiple skins can reference the same pattern, creating a coordinated visual family. The 64 shipped pattern skins demonstrate this approach at various resolutions.

Best practices

  • Always include at least the primary material (Skin_Primary.mat) in every skin bundle.
  • Create secondary materials for every attachment the base item supports.
  • Include a layered attachments material (Skin_Attachment.mat) for attachments with texture masks.
  • Include a fallback attachments material (Skin_Tertiary.mat) as a safety net for uncovered attachments.
  • Test the skin with every attachment type before publishing.
  • Keep skin resolution within the recommended guidelines for the target item size.
  • Respect the original item's silhouette when creating custom mesh overrides.
  • Use the Pattern flag for multi-skin pattern families to reduce bundle size.
  • Follow the curated items color and contrast guidelines even for non-curated Workshop skins.

Frequently asked questions

What items support skins?

Not every item in Unturned™ supports skins at this time. The SDG documentation recommends creating skins only for items that are already skinnable. This includes most weapons along with a few miscellaneous items such as Canned Beans and the Detonator. The unwrapped meshes are included as part of the ExampleAssets.unitypackage provided by SDG.

Can a skin change an item's gameplay properties?

No. Skins are purely visual. They cannot change damage, fire rate, magazine capacity, or any other gameplay property. The skin system is strictly a visual override that replaces materials and optionally the mesh model.

How do I know which ID to use for the skin's ID field?

The skin's ID must match the ID field of the base item. Find the base item's .dat file, read its ID value, and use that same value in the skin's ID field. The skin system uses this numeric linkage to determine which item the skin applies to.

Can a skin have multiple IDs?

No. A single skin .dat file can only target one base item ID. If you want the same visual appearance on multiple items, you must create separate skin assets for each target item ID.

What is the difference between Skin_Secondary and Skin_Attachment?

Skin_Secondary_#.mat is an attachment-specific material for a particular attachment identified by its legacy ID. Skin_Attachment.mat is a layered attachments material used when a secondary material has not been provided for an attachment that has texture masks. The layered material combines the skin's colors with the attachment's texture-masked areas.

Do I need a prefab for a skin?

Only if the skin includes a custom mesh override. Skins without custom meshes only include material files. The vanilla skin system uses the base item's prefab and applies the skin's materials over it.

Can a skin override only some attachments?

Yes. Create Skin_Secondary_#.mat files only for the attachments you want to override. Attachments without a matching secondary material will use the layered attachment material or fallback material depending on availability.

How do custom mesh overrides work with attachments?

Custom mesh overrides must maintain attachment compatibility. The attachment points (sight, tactical, grip, barrel, magazine) must be present and correctly positioned on the custom mesh. The official documentation recommends that custom mesh skins respect the original item's silhouette and ensure attachments still look good when attached.

What is the Skin_Pattern folder structure?

Pattern skins store their texture in a shared pattern folder under Skins\Patterns\<PatternName>\. Multiple skin assets can reference the same pattern through the Pattern flag in their .dat files. The 64 shipped patterns include patterns like Aces, Arctic, Black, Blue, and many others.

Can I submit a skin to the Steam Workshop without a custom model?

Yes. The majority of submitted skins do not include custom mesh overrides. They only include material files that replace the base item's textures. Custom mesh overrides are an advanced option for skins that change the item's shape.

Advanced considerations

Texture masking for skins

Items can optionally include Albedo_Base.png, Metallic_Base.png, or Emission_Base.png textures in their asset-bundled files. When using certain skins, those parts will be masked out and retain their original material. Texture masking is rarely relevant for modders creating their own items but is important for skins that interact with the base item's texture channels.

Skin material setup in Unity

The Unity project structure for skins separates source files from bundle files. The recommended organization is to place source files in Assets/Game/Sources/Items/ and bundle files in Assets/CoreMasterBundle/Items/. For skins, the material files and any override meshes go in the bundle directory.

Cross-mod skin compatibility

A skin created for a mod item must be installed alongside that mod item. The skin's ID linkage tethers it to the specific base item ID. If the base item mod is not loaded, the skin asset loads but does not appear on any in-game item because no entity matches its ID.

Appendix A: Skin .dat template

GUID <32-character-hexadecimal>
Type Skin
ID <base-item-id>

Appendix B: Skin .dat template with attachment slots

GUID <32-character-hexadecimal>
Type Skin
ID <base-item-id>

Sight
Tactical
Grip
Barrel
Magazine

Appendix C: Skin .dat template with pattern

GUID <32-character-hexadecimal>
Type Skin
ID <base-item-id>

Pattern

Appendix D: External references

Shipped skin ID reference

The following table documents the base item IDs that are commonly used as skin targets. The complete list of 74 base item categories with skin support is available in the Bundles\Skins\ directory.

Skin folder nameTarget item description
AceAce weapon
AugewehrAugewehr weapon
AvengerAvenger weapon
BaneBane weapon
BatBaseball bat
BluntforceBluntforce weapon
Bow_CompoundCompound bow
BulldogBulldog weapon
Canned_BeansCanned beans consumable
CardPlaying card weapon
CobraCobra pistol
ColtColt pistol
CrossbowCrossbow weapon
DetonatorDetonator item
EaglefireEaglefire rifle
GrizzlyGrizzly sniper rifle
HeartbreakerHeartbreaker weapon
Hell_FuryHell Fury weapon
HoneybadgerHoneybadger weapon
MaplestrikeMaplestrike rifle
MatamorezMatamorez weapon
NightraiderNightraider weapon
NykorevNykorev weapon
PeacekeeperPeacekeeper weapon
SabertoothSabertooth weapon
SchofieldSchofield weapon
SnayperskyaSnayperskya weapon
SpecOpsSpecOps weapon
SpyglassSpyglass weapon
SwissgewehrSwissgewehr rifle
TimberwolfTimberwolf weapon
ViperViper weapon
ZubeknakovZubeknakov weapon

Authoring checklist

Before publishing a skin asset, confirm the following:

  • [ ] Type is set to Skin
  • [ ] ID matches the base item's ID exactly
  • [ ] Skin_Primary.mat is included in the bundle
  • [ ] Secondary materials are created for each supported attachment
  • [ ] Layered and fallback materials are included
  • [ ] Custom mesh override (if used) respects the original silhouette
  • [ ] Textures follow the curated items resolution and color guidelines
  • [ ] Master bundle includes all material files
  • [ ] Tested in-game with the base item and all attachment types

Glossary

TermDefinition
SkinA visual-only asset that overrides a base item's material and optionally its mesh.
Primary materialThe main material (Skin_Primary.mat) applied to the item body.
Secondary materialAn attachment-specific material (Skin_Secondary_#.mat) for a particular attachment by legacy ID.
Layered attachments materialA material (Skin_Attachment.mat) used for attachments with texture masks.
Fallback attachments materialA material (Skin_Tertiary.mat) used when no other attachment material is applicable.
PatternA shared texture used by multiple skins through the Pattern flag.
Custom mesh overrideA replacement mesh (Override_Mesh_#.prefab) that changes the item's 3D model.
ID linkageThe numeric ID field that tethers a skin to its target base item.
LODLevel of detail - different mesh resolution used at different camera distances.
AlbedoThe base color texture of a material.
MetallicA texture channel controlling how metal-like a surface appears.
EmissionA texture channel controlling self-illumination of a surface.
Texture maskingA system where certain areas of a texture retain their original appearance under a skin.
StockpileThe in-game item store where curated skins and cosmetics are sold.

Cross-references

Skin asset performance considerations

Skin assets primarily impact the game's rendering pipeline and memory usage. Understanding these impacts helps mod authors create skins that perform well.

Material memory

Each skin material file adds to the GPU memory footprint. A skin with four material types (primary, secondary, attachment, tertiary) requires more memory than a skin with only a primary material. The difference is typically small (a few hundred kilobytes per skin) but can add up across many loaded skins.

Texture resolution impact

Higher-resolution textures produce sharper visuals at a higher memory cost. The SDG curated items guidelines recommend 2048x2048 textures scaled to 1024x1024 for large items and 1024x1024 scaled to 512x512 for small items. Following these guidelines ensures reasonable memory usage.

Custom mesh overhead

Skins with custom mesh overrides add geometry to the rendering pipeline. The official documentation does not specify a polygon budget for skin custom meshes, but following the base item's polygon count is a reasonable guideline. A custom mesh with significantly more polygons than the base item's mesh may impact performance on lower-end hardware.

Pattern texture sharing

Using the Pattern flag allows multiple skins to share a single texture, reducing overall memory usage. The 64 pattern skins in the vanilla game demonstrate this approach at scale.

Document history

VersionDateAuthorNotes
1.02026-07-2657 StudiosInitial publication. Complete Skin asset field reference, four material types, ID linkage, pattern system, custom mesh overrides, curated items guidelines.