For sale is a SET OF 4. COLSON 4" Series Swivel Casters With Tech-Lock Brake WHEEL 2" WIDE Mounting 2 7/8"x3 3/8" Capacity up to 1250 lbs each Constructed of durable, light-weight engineered thermoplastics, this brake is ideally suited for wet or corrosive conditions. The simple toe operation holds heavy loads securely. With an advanced brake pad design, the brake holds a variety of wheel types. Only two moving parts. The Tech Lock brake provides virtually maintenance free operation with two moving parts.