Slipstick CB845 3-1/4 Inch Bed Roller / Furniture Wheel Gripper Caster Cups (Set of 4) Chocolate Brown Color Locks furniture wheels in place with patented, cup design that cradles roller and bed caster wheels Ideal for large furniture like beds, pool tables, pianos and dressers each cup can support up to 550 lbs. Protective O-ring bottom protects floors from indentation or damage while holding furniture in place Caster cups are ideal for 2" diameter (50 mm) roller bed wheels up to 2-1/4" wide Simply insert cups under furniture and start protecting your floors instantly