The Troy Industries Railed Gas Tube will fit Russian, Romanian, Bulgarian, some Chinese, US and Others AKs (stamped and milled) with a standard length gas tube. Handguards will fit stamped receiver AKs (not milled receiver). Will work with some Bulgarian, Romanian and Egyptian lower handguard retainers. Others may need some minor modification to fit properly. The railed gas tube replaces factory handguards easily with no gunsmithing required. Cooling holes allow the rail to run cool, even after extended firing. Machined from hardened aircraft aluminum with stainless steel components and finished in MIL-SPEC hardcoat anodizing. Picatinny Rail section allowing the user to attach optics and accessories.