All singlets, from any brand or manufacturer, are permitted for use in competition as long as they meet the following criteria: The singlet consists of a single piece of single ply material that is non-supportive. No seams or stitches that are deemed to be supportive are permitted. The singlet must not be excessively lose and may not have any patches or padding. Any color singlet can be worn. No pockets, zippers, buttons, collars, or reinforced seams are allowed. The singlet may bear the badge, emblem, logo and/or inscription of the lifter’s nation, national association, or sponsor. That which is offensive or liable to bring the sport into disrepute is not allowed. No part of the lifter’s costume can bear the name, logo, or image or any other powerlifting organization, other than the USPA/IPL and its affiliate countries. It's okay for the crotch area to be reinforced as long as the area of the reinforced area does not exceed 12 cm by 24 cm. It has to have legs, which must extend at least 2 inches from the crotch and should not extend past the mid thigh. No references to steroid or drug use. There's a few other tiny odds and ends that you can read up on in the official rulebook, but those are the biggies. If you buy a singlet from any semi-reputable manufacturer you'll be fine.