This Winchester manufactured sixth variation 30-B series rear sight leaf with the "U" shaped sighting notch, 1" side wings, and lacking the patent dates is for the later manufactured model 1906 slide action rimfire rifle. The condition is very good exhibiting a mixture of original blue finish with a brown patina and light wear. (file photo)

Note: Winchester model 1906 takedown slide action rifles with the following serial numbers have been observed with this part:

600K: 655997

700K: 785298