- Complete M16 bolt carrier group assembly
- The QPQ nitride/melonite treatment hardends the surface to 70 RC and reduces friction as well as adding corrosion resistance inside and out
- Superior to chrome lined and parkerized bolt carrier groups
- MPI tested and marked. 9310 bolt nitride/melonite treated with additional cryo freeze for extra strength
- Requires very little lubrication and has a very slick surface
- Corrosion resistance inside and out
- Side staked gas key with grade 8 fasteners