The DS Arms Low Mass ESC - Enhanced Sand Cut complete bolt carrier group is the pinnacle of AR15 - M16 bolt carrier group production. They took their standard Mil-Spec bolt carrier group and upgraded with real world no-nonsense features that make sense, not just make it flashy! First and foremost, they looked to their roots in the FAL Battle Rifle and incorporated L1A1 style sand cuts on the all of the load bearing surfaces of the carrier. These sand cuts allow any sand, dirt or debris that may have gotten into the action to easily be cycled out. DS Arms machines these assemblies using the latest manufacturing techniques, material and finishes. The carrier is machined from 7075 T-6 Aluminum and the bolt is MPI 9310 material. This complete M16 Cut Complete Low Mass Aluminum Sand Cut Enhanced Bolt Carrier Group includes the complete bolt, complete carrier with properly staked gas key, cam pin, firing pin and firing pin retaining pin. A standard M16 Cut Bolt Carrier Group weighs in at 0.7152 pounds, making the Enhanced Low Mass Aluminum Bolt Carrier Group nearly 7 ounces lighter Due to the variations in gas system lengths, gas port diameter and ammunition DS Arms recommend using H1 or H2 recoil buffers for optimal reliability, if your barrel has a proper gas port size carbine buffers can also be used. Available with either a Nitride or Nickel Teflon finish.