Stainless Steel Parallel Key can be of rectangular or square section uniform in width and thickness throughout. The Parallel Key is used where the pulley, gear or other mating piece is required to slide along the shaft. The Parallel Key is made using quality grade material such as stainless steel. The Stainless Steel Parallel Key is available in various sizes such as 1/4" X 1/4", 1/2"X 1/2", 3/8"X 3/8", 5/8"X 5/8", 3/16"X 3/16", 1" X 1" etc.