The Body Solid ProClub Line 210lb Stack Leg Extension Machine will help you build muscular legs and stronger knee joints. Its constructed details include a 2"x4" high-tensile-strength steel mainframe, nylon-coated, self-lubricating, aircraft-quality steel cables. It features fiberglass-reinforced nylon pulleys with v-grooved channels, machine-drilled weight plates that employ oversized nylon bushings for super-smooth operation, and highly polished, chrome-plated steel guide and selector rods. This machine comes with a 310 Lb weight stack. It has a double powder-coated finish that protects against scratching, chipping, and peeling. It also features pop pin adjustable foot pads to assure proper alignment and hold down grips for stability.