[Unique rubber caster cup design] It can lock the furnishings or mattress wheel in place, whereas retaining the hardwood, ceramic tile, linoleum and surface floor from the indentation of the bedroom or domestic furniture. Safe and effective, appropriate for any floor-hardwood, linoleum, laminate, ceramic tile, carpet, etc.[Unique anti-skid design] The bottom is smooth, utilizing electrostatic adsorption technology, so that the furniture casters can slip on the wood floor or tender surface. Therefore, it is hard to move at the floor and has a lot of friction.[Size] 8 black furnishings coasters are round 3 inches (approximately 7.6 cm), which is awfully appropriate for almost all furnishings rollers-1.8 inches vast (approximately 4.8 cm), intensity 0.2 inches (approximately 0.5 cm). eight non-slip caster cups, every single cup can keep 550 pounds (250 kg).[High-quality uncooked materials, smooth to use and clean] The caster cup is made from rubber material, no odor, no injury to the human body, and durable. Simply slide below the mattress wheels or furnishings legs to instantly protect your surface and maintain the furniture still. Easy to scrub and may be cleaned with water.[Wide vary of applications] This fun stopper can suit your bed, geared up with wheels, couches, chairs, sofas, recliners, desks, dressers, pianos, sofas, mattress frames. Our rubber caster cup will quit it all at once!colour: blackMaterial: rubberPackage Contents:8 x floor non-slip padsOnly the above kit content, other merchandise will not be included.Note: Light capturing and diverse exhibits can cause the color of the thing in the photograph a bit varied from the real thing. The size allowed error is +/- 1-3cm.