Elevens 4-Tier Open Shelf, Industrial Vintage Standing Storage Units, Black 18mm E1 grade MDF with black finish, 100lb load capacity per tier 30x15mm cold rolled square steel tube with durable powder coat finish 13" clearance between shelves and 11.8" depth holds larger books for convenience Overall size: 41W x 13.2D x 55H, Net weight: 52lb Working as an artwork display rack by grouping two or more together