This style lock was made by Jacob Dickert of Lancaster County, PA circa 1755-1822 and was used not only by himself, but by rifle builders Vernon , Rupp, Moll, Knoll and others. Lock features traditional hook type springing, bearing surfaces on tumbler and sear, waterproof pan and cam action. Plate is 5 3/8” X 15/16”. Highly polished internally. Recommend ¾” flint.