Caliber: 5.56 NATO, .300 BLK. 16.1” barrel. Similar to the MPR model, with an 11” aluminum free-floated handguard. Magpul M-LOK accessory attachment slots at the 3, 6, and 9 o'clock positions with additional slots on the angled faces near the muzzle. Introduced 2016. .300 BLK chambering added in 2019. SEE POLITICAL PANIC PRICING.