These are four bases for 9mm bullet casings that will fit into an Xbox 360 controller. Just cut down your casing to desired height then a dab of superglue will hold it on. Let me know if it works for you guys. BTW the bases might be a tad snug, when assembling your controller back out the screws behind the buttons to get desired clickyness.The base is a hair too thick so you may want to squish the geometry down a few clicks. let me know if this works or if someone could remix it. Thanks!