Mastercraft seats are made from high-quality Rogue Naugahyde with a center insert of close-weave nylon fabric and slots for a 5-point harness system. Optional grommets in the cover provide a bellows action to keep you cool. Many colors are available to complement or contrast any racing color scheme. Polyurethane foam of differing thickness and density is glued to the liner and built up to achieve desired shape. Mastercraft will custom-fit any seat to assure correct body contour and driving position.All stress points are double-lapped and grommeted for max strength. Liner is attached to frame and tied with nylon parachute cord.Your Mastercraft seat may be ordered with optional lumbar support. Fitted to seat frame, it offers up to 3" of adjustable lumbar support, and adjustment knob may be attached to right or left side.Suspension liner is made of a nylon-coated textile mesh that provides extreme strength and durability. The porous mesh will breathe and allow moisture to pass through. Mastercraft's rugged seat frames are constructed with mandrel-bent and Mig-welded 3/4" mild-steel tubing (.065" wall, HREW 1010).