The Ergo Grip Modular Free Float KeyMod Rail System provides a 2eee outside diameter and a generous 1.8eee inside diameter designed to accommodate most suppressors while maintaining a clean and sleek profile. Ventilation cutouts aid in rapid cooling, and provide substantial weight reduction. Features integral anti-rotation tabs. KeyMod slots located at 3, 6, and 9 oeeeclock positions allowing users to run with or without rails covers. The rail provides multiple attachment locations for Ergo KeyMod accessories including Ergo WedgeLok slot covers and as a host to other KeyMod compatible products. Installation is simple using the standard USGI barrel nut wrench (not included), all necessary mounting hardware is included.