Detailed Product Description 1. 100kg Four Wheels Steel Platform hand truck:Max.rated load:100 ... 6200 & 6303 ball bearings, Precision bearing clearance standards, Let castors more lubricating, Rolling resistance is low, Noiseless.8. Caster Rubber ... : Japanese standard compounding. Natural rubber and other materials make wheels have good flexibility, wearproof,no drag marks, impact resistance ...