This is the hard to find  ORIGINAL sling swivel BASE  only. It is placed on the buttstock of the Winchester 1866, 1876, 1873, 1892, 1894 and 1895. lever action also  model 70   71 and other model bolt action Some of the models came standard with this from the factory and some it was an upgrade option. It is held onto the buttstock with 2 screws, part number 626A, and used the wire loop part number 644. Some models used a loop and J shaped hook on this base.