This Marlin manufactured breech bolt assembly with style No. 6 striker knob and later variation extractor is for the Glenfield model 20 bolt action rimfire rifle with the full length extractor groove along the inner left side wall of the receiver and is in very good condition with honest wear. This bolt assembly has a left side extension that protrudes out near the front portion and fits the extractor groove mentioned. (file photo)

Note: Marlin Glenfield model 20 rimfire rifles with the following year/serial number have been observed with this part:

1974: 26538478