The below capacity ranges indicate the working (dynamic) load that each caster will support. A safety factor should be included in your formula to determine your required load rating per caster.

W/(C-1)=R W is total weight needed to move. C is total number of casters required. R is ideal load rating, with safety factor built in. Divide the total load weight by one less caster than you will use to safely determine load rating.

DuraStar Rubber Casters w/ 4" Wheels · 4 Styles · Up to 450 lb · Ref 209

Plate sizes: 4 x 4-1/2Bolt holes: 2-5/8 x 3-5/8Diameter: 4 inTread: 2 inCapacity: up to 450 lb

Match a 4 x 4-1/2 top plate when bolting casters under finished floors and quiet institutional carts. You will see wheel diameters 4 in, rubber treads, and capacities 450 lb across the SKUs listed below. Bring plate and stem measurements when replacing unmarked casters so the new corners sit level. Softer treads quiet finished floors; harder compounds last longer on chips, heat, and rough concrete.