Colson® Series 4 Standard Duty Casters are some of the most popular casters found in the industry because of their ability to handle up to 900 lbs per caster(3600 lbs for a set of 4!). Available in both swivel and rigid designs. Standard features include: Zinc plated finish, double hardened raceways, 1/2" axle with zerk grease fitting, 1/4" steel top plate, permanent rivet king construction with 5/8" diameter rivet. Options: Brakes, wheel thread guards, 4-position swivel lock and sealed swivel raceway. Up to 9 different wheel types available to fit most any application in sizes ranging from 3-1/4" x 2" up to 8" x 2".