These components called trouks are mainly used in leather products to ensure fitting. There are 2 groups, one is matted on the moving side of the leather and the other on the stable side.You can find it on bags, wallets, mobile cases and other similar products.This parts are Designed in Solidworks and rendered in Keyshot. I have included a STEP file of the assembly and a BIP. file of the some indicative pictures. I Hope you enjoy it!
STP (STEP, filesize: 7.21 MB), BIP (KeyShot, filesize: 7.21 MB)