This Winchester manufactured first variation synthetic rear sight assembly is for the early model 290 semi-auto rimfire rifles with serial numbers below 350,000 and mounts using a single screw (sold separately) instead of the later dovetail style sights. This rear sight assembly is in very good condition with light wear and fading. (file photos)

Note: Winchester model 290 semi-auto rimfire rifles with the following serial numbers have been observed with this part:

No Prefix: N.S.N. & 167977

B Prefix: