Developed by BSA and Captain H.C. Boys under the name "Stanchion" and renamed on acceptance in 1937, the Boys Rifle fired a proprietary 55 caliber armor piercing round. Many were converted to 50 BMG after WWII, with few left in the original 55 Boys and fewer still brought back to the States. This example bears a "SA" cartouche, the acceptance proof of the Army of Finland. Though technically aligned with Nazi Germany and the Axis, Finland received material support from some Allied nations during the Winter War with the Soviet Union. Fitted with the early "circular" muzzle brake left-offset blade front and two-position elevation adjustable peep sights and a top loading Bren-style magazine. The barreled receiver is installed in a steel frame with integral shock absorber, folding "T" shaped monopod, hardwood cheek rest and rear pistol grip, and a canvas shoulder pad with integral oiler.