Mike Covington, the 1919 Hawkins patent was, as Drew says, for the trestle pad. I guess it could have been on the market before the patent was applied for in September of 1919. The patent for the No Shoc was 1922 as stamped in the pad. An original high condition No Shoc is a wonderful pad for a small frame Fox because of the small plugs and the spacing of the screws. A worn No Shoc or Winchester 1922 pad makes a nice imitation Silver pad if the logo is ground off.