Disc Spring, Poly Wave Compression, 17-7 PH Stainless Steel, Thickness 0.010 In, Overall Height 0.300 In, For Hole Size 1/2 In, For Rod Size 1/4 In, Load 10 Lbs, Deflection @ Load 0.186 In, Spring Rate 54 Lbs/In, Meets/Exceeds AISI Type 17-7 PH