Disc Spring, Belleville, 302 Stainless Steel, Min Inside Dia 0.505 In, Max Outside Dia 1.000 In, Thickness 0.043 In, Overall Height 0.071 In, Load 250 Lbs, Deflection @ Load 0.014 In, Flat Load 431 Lbs, Meets/Exceeds ASI 302 and Government AMS Type 302, Package 12