M249 Hollow Grip Bolt and Nut Air Lines The CO2 configuration comes with

The CO2 configuration comes with a different rail that allows it to accept our 12g or 33g CO2 Inserts which makes it possible to use traditional Milspec buttstocks

GEN2 and GEN3

but in a modular configuration that has been designed to fit all Milspec stocks as well as most AEG stocks

so thank you for making thoughtful purchasing decisions

M249 Hollow Grip Bolt and Nut Air Lines The CO2 configuration comes withThis bolt and nut comes standard with our M249 series HPA engines and replaces the original grip bolt in your A&K or Classic Army M249 Mk46. The bolt being hollow allows the air line to pass through the center of the bolt so the air line can exit the replica through the grip instead of needing to drill a hole in the gun's body.