[HARD PLASTIC MATERIAL] The adjustable furniture risers are made of heavy-duty sturdy hard plastic that can to the weight of the heaviest furniture in your home or office, they can safely support a of 20,000 lbs. They 't crack like other risers. High-density bottom felt pads protect your hardwood, tile linoleum floors and carpets from scratches and . [Protect Your Hard Floors From Scratching] The bottom of the sturdy sofa leg riser is made of high-density felt furniture pad bottom, and the bottom felt pad protects your floor from scratching. Heavy duty and edges can hold weight safely without causing any dents or cracks on hardwood or hard surfaces. Protect your hardwood, tile and linoleum floors from damage and wear and tear. Advantages -- sofa risers not only give you more storage space, also easier for the elderly to in and out of bed. The added height allows the vacuum cleaner or robot vacuum cleaner to work more flexibly. Colour:black Material:Plastic Package Contents: 4 x Adjustable Bed Risers Only 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.