- Wholesale 4" SWIVEL CASTER RUBBER - 4" x 1.5" - 220 Lbs Capacity. - Solid Rubber Tire Bonded to Cast Steel Wheel. - With Zerk Fittings for Easy Greasing. ⚠ WARNING: This product can expose you to DEHP, which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.