The No-Tip Block is constructed with a dense light-weight foam and then topped off by a soft, high quality foam making it sturdy yet comfortable. Its unique design allows weight to be distributed evenly keeping it from tipping like most foam ottomans. Sterling is a polyester with a soft hand and linen like texture that is easily removable for washing or a quick trip to the dry cleaner. Get the Tray Accessory that when fitted on the top, turns this piece into a side table in seconds! Move to the bottom of the piece and use as a base, for when extra seating is needed.