The space you need and the height you want. This multi-height AV cart includes three large shelves that can hold up to 400 lbs. (evenly distributed) and multiple leg sets that allow you to build the cart to the height of your choosing from 27" to 54" high. The shelves are made of a molded plastic that won't scratch, dent, rust or stain, and feature a .25" retaining lip. This mobile cart has a push handle molded into the top shelf and four heavy-duty casters, two with locking brake), making it easy to maneuver.