Specifications:- Shaft Dimension (with gear) (LxWxH): 13 1/8" x 3 1/4" x 2 3/8" (33.4 x 8.3 x 6 cm)- Shaft Dimension (without gear) (LxWxH): 13 1/8" x 2 3/8" x 1 11/16" (33.4 x 6 x 4.3 cm)- Bracket Dimension (LxWxH): 18 1/8" x 1 3/4" x 9 15/16" (46 x 4.5 x 25.2 cm)- Chain Length: 72 1/16" (183 cm)- Suitable Backdrop Pole Inner Dia.: 1 7/8" to 3 1/16" (4.8 to 7.8 cm)- Load Capacity: 22.05 Lbs (10 kg)- Material: Metal Brackets, Nylon Rollers and Chains- Net Weight: 14.55 Lbs (6.6 kg). Package Contents:- 2x Brackets- 8x Shafts- 4x Weights- 4x Chains- 8x Expansion Screws- 1x Manual. Notice: - For safety purposes, if you need to mount on the ceiling, it is suggested that the ceiling should be a concrete structure instead of wood ceiling or other structure that not solid.