The sled is driven by nylon bearing wheels that provide an ultra smooth and quiet ride. The carriage holds 8 wheels that hug the solid steel guide rods preventing lateral movement and providing a precise motion from top to bottom. The seat and adjustable back pad along with the adjustable angle foot plate and hand grips lock the user into and perfect position to perform the exercise. The design of the carriage and seat section allow for a leg sled that is significantly more compact than any other in it?s class. A foot tube is also included to provide calf raises.