Trijicon ACOG Tall Quick Release Mount for Compact Tall Quick Release Mount for 1.5x16, 1.5x24, 2x20, 3x24 and 3x30 ACOG Models  Fits 1913 Rails Precision CNC machined from a block of 6061 T6 aluminum Finished in 3 mil-spec anodized black for a rock hard finish Height of mount surface to optical axis: 1.660 in. Weight: 3.0 oz.