Product DescriptionThe Strike Industries R.E.X. Riser is a low-profile, lightweight Picatinny riser designed for AR-platform rifles. Optimized to achieve ideal co-witness height when paired with the SI Reflex Exoskeleton (R.EX) mount, it works with A2-height sights using the included spacer or with Sidewinder sights without the spacer. Machined from durable 6061T6 aluminum with a Type III hard anodized black finish and secured by a steel clamp and hardware, this 3-slot riser provides a solid mounting platform for a wide range of Picatinny-compatible optics. It measures 2.09 inches in length, requires five rail sections for proper mounting, and weighs only 2 ounces.Product Highlights Low-profile 3-slot Picatinny riser for AR platforms Co-witness ready with SI Reflex Exoskeleton mount; spacer included for A2-height sights 6061-T6 aluminum base and spacer with Type III hard anodized finish Height options of 0.53-0.63 inches depending on spacer; R.EX Exoskeleton adds 0.2 inches Lightweight 2 oz design; requires five Picatinny rail slots to install Specs Model: R.E.X. Riser Color/Finish: Black, Type III hard anodized Materials: Base & Spacer - 6061T6 aluminum; Clamp & Screws - Steel Weight: 2 oz Heights: 0.63 in with spacer; 0.53 in without spacer; Spacer height 0.10 in Total Length of Riser: 2.09 in Rail Interface: Picatinny; 3-slot design Required Mounting Space: 5 rail sections Compatibility: Optimized for SI Reflex Exoskeleton; universal Picatinny optics Includes: Riser base, riser rail, spacer, clamp, M5x30mm cap head hex screw, 2 x 10x3x.48 mm springs, 4 x M3x6 mm button head screws; medium-strength threadlocker recommended UPC: 708747546972 MPN: REXRISERBK Brand: Strike Industries Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.