The RN8876-M20 from Richmond is a 200mm diameter rubber tyred nylon wheel and has a tyre width of 35mm.The following Richmond castors use this wheel (not necessarily with the same axle diameter) S8050, S8050B.This wheel is designed to suit 20mm axles

The RN8876-50 from Richmond Rolling Solutions is a 200mm diameter rubber tyred nylon wheel and has a tyre width of 35mm.The following Richmond castors use this wheel (not necessarily with the same axle diameter) S8050, S8050B.The axle diameter is 1/2