GHK M4 GBB High Cycle & Speed Bolt Kit - Black

The GHK high-speed high-cycle bolt and spring set is designed to be a drop-in upgrade set that supercharges your GHK M4 GBBR.  The bolt carrier group is ultra-lightweight and the spring strength is perfectly in tune to ensure a rapid cycling response with every pull of the trigger!  

Compatibility: 

• GHK M4 Series GBBRs 

Includes: 

• x1 GHK M4 GBB High Cycle & Speed Bolt Kit - Black
• x1 Buffer
• x1 Spring