Equipped lifters compete separately from raw lifters. Equipped lifters will wear a squat suit, knee wraps, a bench shirt, and a deadlift suit. These four things are what separate equipped lifters and raw lifters. A squat suit is made of an elastic-like material, and a single-ply polyester layer. This allows a competitor to spring out of the bottom of a squat (called "pop out of the hole" in Powerlifting circles) by maintaining rigidity, keeping him or her upright and encouraging their hips to remain parallel with the floor. This allows lifters to lift more weight than would normally be possible without the suit. There are also multi-ply suits giving the lifter even more rigidity, like that of a traditional canvas suit, with the same pop as a single-ply suit or briefs but are exponentially harder to use, and are usually reserved for the top lifters. During the squat, lifters also tend to wear knee wraps. Even though knee wraps will be a sub-classification of raw lifting it will still be worn by equipped lifters. A raw lifter who would squat in knee wraps will have the weight lifted noted as "in wraps" to distinguish this from the other raw lifters. Knee wraps are made out of the same, or very similar, elastic material as wrist wraps are made out of. They are wrapped around the lifters knees very tightly with the lifter usually not being able to do it himself and needing someone to assist them in doing so. The knee wraps are wrapped in a spiral or diagonal method. The knee wraps build elastic energy during the eccentric part of the squat and once the lifter has hit proper depth the lifter will start the concentric part of the movement releasing this elastic energy and using it to help them move the weight upwards. It gives the lifter more spring, or pop out of the hole of the squat resulting in a heavier and faster squat.