This 4" x 1-1/4" polyurethane on plastic standard duty threaded stem caster with tread brake is durable and easy to roll. Polyurethane wheels are excellent for indoor or outdoor use. The caster is retained with a 1/2-13UNC x 1-1/2" threaded stem. Our 25 Series is an economical lineup of casters and wheels designed for a range of applications with load requirements up to 350 pounds. These casters are available in a variety of size, wheel, fastening and brake options, and features a one-year standard warranty.