With a host of improvements on the Gen 1, the Gen 2 CRBN GB now works with the Polarstar Jack and Gate Pulsar engines, has perfect fitment with the Maxx mag release, and allows you to store your FCU and Battery in your gearbox.

This CRBN Gearbox enables you to use a CRBN Upper with ANY V2 airsoft replica engine system! It's now possible to use Polarstar drop-in engines such as the F2, F1, and Jack in your build, as well as the Gate Pulsar!

Expand the capability of your CRBN upper builds with an AirTac Customs CRBN Gearbox!

This AirTac Customs CRBN Gearbox includes:

AirTac Customs CRBN Gearbox:

• Machine milled to perfection
• Included Gate Pulsar Spacers
• Included Trigger Board Screw
• Upgraded Dual Tensioning grub screws to eliminate engine wobble
  
• Gearbox screws for both halves
• Cerakoted Matte black finish
• Allows compatibility of a CRBN Upper with any drop-in HPA engine
• Does not include selector plate

Compatible with:

• [CRBN] G&G-style V2 Lowers (SSG1, ARP9, SSG556, etc)
• Any other V2 lower, upper, and grip.