Slim Rail 12.0 and 15.0.
The SUM Rail 12.0 and 15.0 from Daniel Defense uses the KeyMod accessory attachment system to save weight and improve cooling and ergonomics. The KeyMod is a recoil-resistant, two-part, direct attachment method for accessories that offers "return-to-zero" when accessories are removed and reinstalled. The SUM Rail features the "Bolt-Up" system, which provides modern flattop upper receivers with a free-floating, continuous upper rail platform. Ambidextrous sling swivel attachment points are integrated into both the left and right side rails at 1 and 11 o'clock. It's available in 12- and 15-inch models. For more info: (912) 851-3225, www.gunsmagazine.com/ company/daniel-defense-inc