The Fortis Camber AR15 Rail System featuring Fortis Manufacturing's new Camber Lock mounting system is the next evolution of extremely popular handguards. Built for the end user that requires an even more rock solid platform. The Camber Lock is one of the industries' most solid mounting systems available. The stainless steel barrel nut, locking camber nuts are purpose built for rigidity and weight savings. All of handguard lengths are purposely done to fit specific barrel lengths to maximize handguard real estate Installation only requires a high quality castle nut wrench (not included) and with an included T30 Torx L-Key, you'll lock the rail down in a matter of minute. This rail system is very easy to install and more importantly, remove to service your weapon. MLOK slots in the usual 3, 6 & 9 o'clock positions with additional MLOK slots at the 1:30, 4:30, 7:30 & 10:30 positions for all your light & switch needs. Specifications for Fortis Manufacturing Camber AR15 M-Lock Rail System: Manufacturer: Fortis Manufacturing Color: Black Finish: Hard-coat Type III Anodized Fabric/Material: 6061-T6 Aluminum Gun Model: AR-15 Handguard Type: Free-Float Gun Rail: M-LOK Weight: 2.9 oz Condition: New Features of Fortis Manufacturing Camber AR15 M-Lock Rail System Continuous Top Rail. M-Lok at the 3, 6, & 9 o'clock, additional off-set location at the front of handguard. 6.7in handguard mates perfectly with a 7.5in barrel. 9.6in handguard mates perfectly with a 10.3in or 10.5in barrel. 11.7in handguard mates perfectly with a 12.5in barrel. 13.8in handguard mates perfectly with a 14.5in barrel. 15.3in handguard mates perfectly with a 16in barrel. Package Contents: Fortis Manufacturing Camber AR15 M-Lock Rail System