Whitmor Bed Risers - Black (Set of 4) Increase under bed storage by 5.25 inches Easy to use; simply place under bedposts Make room for storage bins to fit under the bed; store out-of-season clothing, extra bed linens, blankets and more Dimensions: 6.375 x 6.375 x 6 inches Made of durable black plastic resin; add height to your bed without worry of the risers breaking Recessed walls fit up to 2.63 inch bed post and ensures that your bed will not slip and fall Bed risers may be stacked together when not in use to conserve space Whitmor's Service Guarantee - we stand by our products, if you have any problems, contact us for help