The singlet a wrestler wears can play an important role on how they move on the mat to take down their opponent.
 
High cut is very popular at the higher levels more like a standard tank top with slightly thicker shoulder straps and a cut just under the armpits.
The Fila cut is more like a muscle tank top with its lower cut exposing the ribs and thinover-the-shoulderlder straps.
The Low cut which isn’t permitted in most high schools on up has a completely open side that exposes everything and is easy to grab and hold.