Weighted sleds are metal hauling carriers that comes in different shapes and sizes. While some come with wheels and others don't.
The sled is a functional full-body exercise that targets your quads, glutes, hip flexors, calves, hamstrings, core, triceps, chest, and shoulders. You use the equipment for many exercise but they all stem from hauling the sled whether if it's pulling or pushing.
Resistance is added by the amount of weights put on the sled as well as the friction added from the type of sled (Wheel, no wheel) and floor being hauled on.