The Circuit Series Ab Curl Bench utilizes body weight when working out the abdomen. This bench is easy to use and designed to provide an inviting core training option for exercisers. Instructional Placards Easy-to-follow instructions illustrate proper use and muscles trained Belts and Pulleys 4-1/2" (11 cm) and 6" (15 cm) diameter fiberglass-impregnated nylon pulleys feature sealed bearings Cushioning Contoured cushions utilize a molded foam for superior comfort and durability; All edges are stitched to eliminate any folds in the material that would limit durability Shrouds Full front and back shrouds and pulley covers Adjustments No set-up adjustments are required, which ensures ultimate ease of use Lifeband ResistanceSystem Resistance provided by a series of polyelastomer Lifebands, a bound and covered group of elastomer strands Frame Description 11-gauge steel frame ensures maximum structural integrity; Standard rubber feet protect base of the frame and prevent the machine from slip