This Remington manufactured late variation hammer and mainspring assembly is for the model 121 slide action rimfire rifle in 22 S, L & LR caliber and is in very good condition with light wear. This assembly consists of the late variation hammer, hammer pin, mainspring rod and mainspring. (file photo)

Note: Model 121 rimfire rifles with the following serial numbers have been observed with this part: 143356, 162751 & 164006.