This 1800's style lock incorporates a roller on the frizzen spring and a taller hammer to utilize most of the frizzen face and is appropriate for smaller rifles, pistols and fowlers. This is known as one of the fastest locks on the market. Dimensions 5" x 15/16". Chambers has changed and improved this lock for 2014. The most visible change is the re-designed hammer (cock). uses 3/4" flint, #FLINT6E.