Objects used in a lot, clothing used on a sim, the original mesh that is being recolored, etc. This is a dedicated space for artists to list and organize any additional content that is required as a prerequisite for the item in question. Photos from The Sims Resource's post We've added a new tab to the site - you will now see a 'Required' tab on some content. Gotta appreciate the little touches like this. This site will not work without JavaScript.