This is one of the 22 cal conversion kits manufactured by "Erma" that was used in the K98 series of rifles. This kit was designed to replace the entire bolt assembly, floor plate, magazine spring and follower, which allowed field units to use the standard K98 rifle and economical 22 LR ammunition to train with. The kit itself is composed of a complete bolt assembly with barrel liner, new floor plate mechanism (that holds the 22 cal magazine), two magazines and tool, all in a wooden storage box. The bolt assembly is marked with the "ERMA Logo" surrounded by "FABRIKAT" and "ERFURT", and three "Eagle / WaA77" Waffenamt proofs with an eagle firing proof over the serial number. The floor plate and magazines are the earlier versions that marked "ERMA" and a single "Eagle / WaA132" Waffenamt on the back spine of the magazines. The magazines are retained in the floor plate with a side mount spring mechanism. The floor plate is marked "ERMA / ERFURT / 1938" over an "eagle / 77" proof. All visible numbers match.