This Ithaca manufactured bolt spring plunger is for the model M-66 Supersingle lever action single barrel shotgun in 12 and 20 gauge and is in very good condition with light wear. (file photo)
Note: Ithaca model M-66 Supersingle lever action single barrel shotguns with the following serial numbers have been observed with this part:
12 Gauge: 17010 & 53451
20 Gauge: 51645 & 202920