Part assemblies might consist of all subparts in a variable color, one or more subparts in a variable color with the rest of the subparts in fixed colors, or all subparts in fixed colors. Here are examples of completely variable colors, partially variable colors, and fixed colors in assembly inventories:

• Part Assembly with Completely Variable Colors - Hips and Legs - The matching color hips and legs assembly appears in sets in at least forty different colors (in which all subpart colors match), so the inventory of the hips and legs assembly contains all of its subparts in variable colors. The part title for this assembly does not mention any subpart colors. This allows the assembly to be included in many sets without the necessity of a new catalog entry for every color.
• Part Assembly with Partially Variable Colors - Hips and Black Legs - The hips in this assembly are inventoried in a variable color and both of the legs are inventoried as black. The hip color is not identified in the title of the part assembly, but the color of the legs are. This allows hips with black legs to be included in many sets without the necessity of new catalog entries for every color combination.
• Part Assembly with Fixed Colors - Tyrannosaurus rex - The inventories of assemblies which always appear in the same colors in all of the sets in which they appear could include all subparts in fixed colors. The most common uses of fixed color inventories are for animal and figure inventories. The part titles for fixed color assembly inventories may or may not describe subpart colors.

• Minifigure, Torso Assembly - Always include the Pair of Arms entry instead of entries for one left and one right arm. The exception to this rule is when the torso assembly includes differently colored or patterned left and right arms.
• The torso entry in the torso assembly inventory should always be variable color (color ID 0).
• A stickered torso assembly should have a stickered torso (not a plain torso) in its inventory.
• The inventory add page for torso assemblies will have some of the fields pre-filled for your convenience. You may delete or change any of the pre-filled entries as you deem appropriate.
• Special Assembly - Always include everything in the assembly that is included in the set instructions and catalog image of the assembly. This includes stickers applied to subparts and a single projectile for each projectile shooter. Some subparts of the assembly may not be attached by any connection points but are considered an integral part of the assembly.