Paddle lever controls for 10° seat tilt and 22° backrest tilt Ergo knob controls 5" backrest height adjustment 5-leg, 26" diameter tubular steel base with 2.5" high-impact nylon glides Optional tubular inserts 5130, carpet casters 5131, hard floor casters 5132, floor glides 5138, closed loop 5143 and t-pad 5144 armrests available (sold separately). Ergonomically correct high, mid and low-rung polypropylene footrests