This is a Marble Arms tang sight (aka Peep Sight) Winchester model 71. It comes with 3 different sight apertures (1/2 inch diameter with .055 hole; 1/2 inch diameter with .102 hole; 3/4 inch diameter with .032 hole). Hole spacing on the base of the sight is 2.185, and the height adjustment is 1.680 inches to 2.015 inches, with a 18 degree angle. Mounting screws are NOT INCLUDED with the tang sight, so if you need those screws they can be purchased in the option box below. If you have a short tang model please see st9828
