The SOCOM Gear 12" Daniel Defense RIS II is a replica of the MK18 rail system used by the Navy Seals. This RIS features full MK18 trademarks including NSN numbers and cage code numbers. The RIS is machined from high quality aluminum and hard coat anodized for a stylish and protective finish. This is a unique 2 piece free float rail system. The Daniel Defense RIS II is two piece so it can accommodate a barrel mounted M203 launcher. SOCOM Gear is leading the way for fully licensed high quality airsoft accessories.