Disc Spring, Belleville, 302 Stainless Steel, Min Inside Dia 0.531 In, Max Outside Dia 1.125 In, Thickness 0.062 In, Overall Height 0.083 In, Load 520 Lbs, Deflection @ Load 0.017 In, Flat Load 73 Lbs, Meets/Exceeds ASI 302 and Government AMS Type 302, Package 6