Original side plate (lock plate) rear screw. For M1855, M1861, Special Model 1861, M1863, and M1864 Springfield’s. They were also used on Model 1866 – 1870, 50-70 caliber Springfield Muskets & Rifles. This is used to attach the lock to the stock.
Note: These are original parts for original muskets and may not fit reproduction guns. Conditions vary but all are serviceable . No returns.