The Middle Atlantic RKW-HD is a caster kit designed to be used with laminate racks. The kit includes four casters, two of which are locking, and has a weight capacity of 150 lbs. The casters add 2-3/4 inches to the overall height of the rack system, making it easier to move and maneuver. The RKW-HD is sold as a set of four and is easy to install. It is a durable and reliable solution for adding mobility to rack systems, allowing them to be easily moved and repositioned as needed.The Middle Atlantic RKW-HD is a caster kit designed to be used with laminate racks. The kit includes four casters, two of which are locking, and has a weight capacity of 150 lbs. The casters add 2-3/4 inches to the overall height of the rack system, making it easier to move and maneuver. The RKW-HD is sold as a set of four and is easy to install. It is a durable and reliable solution for adding mobility to rack systems, allowing them to be easily moved and repositioned as needed.