Features. Mobile Chrome Wire Shelving stem caster carts add versatility & flexibility to any operation, creating a transport system.. The bottom solid shelf on cart prevents dust and other contaminants lifted off the ground from entering below while the unit is in transit.. Unit consists of 4 - posts, 4 - Wire shelves, 4 - donut bumpers and 4 - 5 in. poly stem casters, 2 with brakes.. Size - 63 in.. Capacity - 800 lbs.