The two 5 x 1.25" Caster with Brake for R8 and R10 Carts from MultiCart are designed to fit these carts, and include the nuts and locking washers to secure them in place. Furthermore, each yellow caster hub is made of a polymer that is bonded to the TPR tread.
Compatibility
R8 and R10 carts
UPC: 672485350804