This CDR-15 rifle is in 300 AAC caliber, and is a quick bread down rifles that fits in the same small hard case as other DRD rifles. The advantage of the DRD no tool, quick change barrel is that the shooter can switch calibers in less than 1-minute without any tools. For mounting, the CDR-15 rifles come with a MIL-STD 1913 rail. This rifle also features a Magpul CTR stock, MOE grip and billet receivers. This CDR-15 has a black hard coat anodized finish.