This Lyman manufactured No. 1A folding tang peep sight with locking lever and small turn down peep is marked on the underside of the base with a "WS" indicating that this sight is for the Winchester model 1890 takedown slide action rimfire rifle. The overall condition is very good to near excellent retaining most of its original blue finish with light wear and a few freckles of rust staining. The mounting screws are not included.  (file photo)