QUESTION: We have an extra piece that wee are not quite sure what it is. It is black heavy plastic, about an inch tall and looks like it's made to fit on one of the bars. It has a screw in the top like it may be meant to be tightened down. Please let me know what this is and how it works. Thanks ANSWER: The black piece that snapped in one of the back brace with a screw is for the purpose of hanging the cut-out piece only. When people are using the cut-out hole, they remove the cut-out piece and hang on that screw. That is all it does, nothing need to be adjust. For more discussions, options and details about the product, or to order the product, please click here New release: uniquely designed with the combination of swivel and cut-out seat to meet special needs of patient care. The sliding and swivel functions and double safety locks make shower easier and safe. Easy to clean and dry. Shipping is free. Sliding transfer bench with uniquely designed swivel cut-out seat enables user to turn every 90 degrees before getting in and out of the bathtub or shower. Removable center piece switching to cut out seats. Makes patient transfer even easier and safer. Height adjustable in 1/2" increments. Bench slides for easy mobility. Splayed leg configuration for added stability. Plastic model seats have a larger seating area and come with a Shower Head Holder. Seat and backrest have a non-slip texture finish. Safety belt is included. Backrest can be installed on either side of seat. Durable lightweight aluminum frame. Secured locking mechanism for both patient transfer and while in the tub/shower. Come with double safety locks. Seat Width: 20.5" Seat Depth: 13.5" Seat Height: 20.75" - 25.25" Actual Slide: 15" Rail Length: 29.625" Base Width: 36.75" - 37.5" Base Depth: 18.25" - 19" Back Height: 12.5" Required Clearance: 14" - 18.5" Weight Capacity: 400 lbs.