【universality】- the mobile roller is used for the bottom of appliances like portable washing machines, washer and dryer, refrigerator or mini fridge 【product parameter】- height: 3-3/4 inches. weight limit: 300 lbs. includes: 4 locking swivel wheels, 4 sturdy pvc corner pieces, 4 sturdy stainless-steel poles and screw tool. 【adjustable size】- this movable base can be adjusted from 18-1/2 inches to 27-3/5 inches, you can effortlessly roll a wide variety of furniture through your house 【360-degree wheels】- equiped with 360-degree 4 locking swivel wheels, that you can move it easily or lock wheels to make it fixed in order to prevent collision. 【easy to assemble】- the instruction is contained. according to the instruction, you can easily complete assembly. our dolly rollers will be your trustworthy choice.