.45 cm & 60 cm seat come without backrest. .75 cm with backrest is used as transfer bench. .Aluminum anodized frame. .ABS slats. .Folding legs. .KD packing. .Product size: 45 cm: 45x30x36.5-54.5 cm 60 cm: 60x30x36.5-54.5 cm 75 cm: 75x30x36.5-54.5 cm (Transfer Bench with Backrest) .Weight capacity: 300 LBS