Low profile Casters also known as Business Machine Casters and are a class of small but heavy-duty casters to maximize weight capacity and minimize the total overall height of your equipment. Low Profile Business Machine casters are meant to keep your equipment at the lowest possible height while allowing you to roll heavy equipment with ease. Caster HQ has low profile casters to meet your every need, whether it is office equipment, displays, vending machines, copiers, Business Machines, Refrigeration Equipment, computer electrical storage equipment, server towers, and institutional uses such as medical equipment or even theatrical uses. This listing is for a 3" Heavy Duty Swivel Caster with a weight capacity of 1,000 lbs per caster. This set of 4 can withstand up to 4,000 lbs. The wheel is made out of an extremely strong and impact resistant glass filled nylon. All of these casters are powder coated in a black coating for extra protection from rust and debris.