Special Features
Glass, optical, mil-g-174, grade c, type 517-645 or 523-586. Both surfaces polished and coated with magnesium fluoride, rim and chamfers ground. Dimensions, 5.000 in. O/a lg, 3.875 in. O/a w, 0.125 in. Thick, both ends rounded on a 1.937 in. Radius. Two mtg slots along each side of length 0.125 in. W, 0.156 in. O/a depth on 0.625 in. Mtg centers. All edges chamfered 0.010 in. By 45 deg. Furnished with 2 gaskets.
