There were two F.D. Hawkins patents that apply to the pad with the heart-shaped vents -- Patent No. 1,325,152, granted Dec. 16, 1919, which shows a base nailed to the butt (similar to the Huntley/Jostam Sponge Rubber Pad)and the pad glued to that; and Patent No. 1,538,990, granted May 26, 1925, that shows the pad with a fixed base screwed to the butt of the gun.