The Tuff Stuff Gladiator Series ELC-18 Leg Extension/Leg Curl optional attachment helps develop hamstring and quadricep leg strength which is extremely helpful in most major sports including football, baseball, basketball, track and field, soccer, volleyball, tennis, swimming, wrestling, boxing, martial arts and more. Also helps hold users in place during decline exercises including decline chest press movements or ab crunch/sit up training . When used in conjunction with Tuff Stuff Gladiator Series EID-42 adjustable multi purpose bench, the ELC-18 Leg Extension/Leg Curl attachment helps all athletes as part of a total body training program developing functional total body strength as part of their home strength training routines. Performs Quadricep developing Leg Extension movements from a seated position or Hamstring developing Leg Curls from a prone or horizontal position (user is positioned face down facing downwards towards the extended seat pad). Requires loading Olympic weights to be used to create resistance. Warranty: 3 Years Frame, 1 Year All Other Parts.