Matl calcium fluoride uv grade; both surfaces polished, coated for max transmittance 2200/4300 a; sides ground; 0.890 in. L, 0.363 in. W, 0.155 in. Thk max; surfaces not parallel by 3 deg; 0.12 in. W free aperture; champher four edges 0.09 in. D x 45 deg
