This Thompson Center manufactured first variation rear sight windage spring is for the earlier Hawken muzzle loading rifle which uses the first variation rear sight and is in excellent condition having light wear. (file photo)
Note: Hawken muzzle loading rifles with the following serial numbers have been observed with this part:
Percussion: 111807, 130609 & 239982
Flintlock: 11555
Kit in Percussion: K145177 & K188746
Kit in Flintlock: K80324