Plastic Stacking Design: bed risers 8 inch heavy duty provide storage space by elevating the bed with stackable option, and you can also stack them to 3,5 or 8 inch height Size of Sofa Risers: Adjustable bed risers base bed blocks: 6.3*6.3*8inch(L*W*H).Groove depth: 0.65 inch. Actual lift height: 3,5 or 8 inch. The bed frame risers are only suitable for furniture legs smaller than 2.75 inch wide Material: These furniture risers are made of heavy duty plastic, can withstand up to 2000lbs. Ensure to only use these risers with proper installation. Intended Use: Bed risers are primarily designed for beds, and using them for other purposes may cause instability. Include: You will be given a set of 4 bed risers raise your bed frame, which provide more space or make your under bed more easy to clean BTSD-home 4 pack Bed Risers 3,5 or 8 inch Heavy Duty Furniture Risers