[HARD PLASTIC MATERIAL]Adjustable furniture risers made of heavy-duty strong hard plastic, which can stand the weight of the heaviest of furniture in your home or office, they can safely support a of up to 20,000 lbs. They won't crack like other risers. High density bottom felt pads protect your hardwood, ceramic tile linoleum floors and carpet from scratches and scuffs.[UPGRADE SCREW CLAMP FIXED & NOT FALL OFF]You don't worry about bed risers fall off. Other chair risers stickiness is not enough, it is easy to fall off. To solve this problem, we upgraded adjustable bed risers with screw clamp. 3 cm grooves sinking, moving will not tilt. Adjustable sofa/couch/table/desk risers is easy to install. Step 1). Clean table leg and keep dry. Step 2). Center Align Chair Legs. Step 3). Use hexagonal screw to lock. Step 4) Done.[PROTECT YOUR HARDFLOORS FROM SCRATCHES]Strong couch legs risers bottom is made of High Density felt furniture pads Bottom, Bottom felt pads Protect your floors from scratch. Heavy duty and smooth edges would safely handle with the weight without causing any dent or crack on hardwood or hard surfaces. Protect your hardwood, ceramic tile and linoleum floors from marring and scuffs.advantage -- Couch risers not only give you more storage space, they also make more convenient for the elderly to get in and out of bed. And the added height allows vacuum cleaners or robot vacuum work more flexibly.Colour:blackMaterial:plasticPackage Contents:4 x Chair RisersOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.