The RR5077-37 manufactured by Richmond is a 125mm diameter rebound rubber wheel with a top load capacity of 150kg and has a tyre width of 35mm.The following Richmond castors use this wheel (not necessarily with the same axle diameter) S5214, S5214B,

The RR5077-31 from Richmond is a 125mm diameter rebound rubber wheel that can safely take loads up to 150kg and has a tyre width of 35mm.The following Richmond castors use this wheel (not necessarily with the same axle diameter) S5214, S5214B, R5043,