The Daniel Defense DDM4ISR is our Integrally Suppressed Weapon System optimized for the .300 Blackout cartridge. Built around a 9"" Cold Hammer Forged barrel that is fluted along with a target crown and a standard pistol-length gas system" this versatile" high-performance rifle is the complete package" accurately delivering both subsonic and supersonic projectiles downrange with unrelenting reliability. Because the suppressor is an integral part of the barrel" this weapon system is ready for service right out of the box. There's no attaching a suppressor and wondering if it's mounted correctly and/or properly aligned. There's no re-zeroing for suppressed vs. unsuppressed fire. The DDM4ISR's integral suppressor extends the barrel to an NFA-required 16 inches in length" so this platform is not classified as a Short Barreled Rifle (SBR) and therefore only requires a single tax stamp (for the suppressor). The suppressor's lightweight outer tube is constructed of durable" heat-resistant metal alloys and coated with a protective high-temperature Cerakote-C finish" which is able of withstanding extreme temperatures and harsh environments. The suppressor is also user-serviceable" so its baffle core can be easily removed for periodic cleaning in order to maintain peak performance. The DDM4ISR comes standard with Daniel Defense's MFR XL 15.0 modular handguard" which features a continuous 1913 Picatinny rail on its top" for the mounting of iron sights or optics" and Keymod attachment points on the sides and bottom. This longer" multi-functional handguard" in conjunction with a Daniel Defense Buttstock and Pistol Grip" make the DDM4ISR as ergonomic and maneuverable as it is versatile.