Crimson Trace Hardline Pro Black Anodized 4-16x 50mm 30mm Tube Illuminated MR1-MIL Reticle The Crimson Trace Hardline Pro optics are designed with the experienced tactical and target shooter in mind and have been purposefully built from the ground up. The line features Aerospace grade 30mm tubes, medium and long-range optics with a variety of custom reticles, fully multi-coated lenses, nitrogen purged, shock resistant and ready for whatever elements they encounter.