Neewer Photography 4 Roller Wall Mounting Manual Background Support System, including Two(2) Four-fold hooks, Six(6) Expand bars, Four(4) Chains, Ten(10)Clamp Screws Perfect for paper backdrop support system.The included chain is used to raise and lower the paper easily and smoothly and also helps to protect the background from kinking. Substitute of high priced electrical roller system.Takes up a small amount of space when the background is rolled up. Durability & light weight, easy to use.Adjustable friction control to prevent paper roll out. Gear designed roller ensures effortless raising and lowering backgrounds. Counter-balanced chain and gear assembly makes raising and lowering your backgrounds quick and easy.Note:The Background is NOT included.