It's been a long time since we have heard about this product's availability. If you're looking for one, you can find one at RSOV.com where they're selling this for US$187.99... "When you've played airsoft long enough, then most AEG's start to feel the same in terms of the shooting experience and you start craving for more blowback and recoil to add to the experience. This CO2 type gearbox simply replaces the gear driven gearbox in your AEG with a CO2 powered system.

Simply pop in a 12g CO2 powerlet into the pistol grip and pull the trigger. This new blowback system pumps out the BBs at 300fps with blowback kick for realism!

Product Features:

• Gearbox V.2 for Class Army or Marui gun body. (Prefer metal body)
• Steel trigger + Steel charging handle.
• Default velocity: 300ft/sec (Upgradeable)
• Blow back single shot action. (Just like paintball gun's action.)
• Semi auto (Upgradeable) (electronic trigger under development.)
• 12g CO2 cylinder in your grip. (~70-80 shots depend on pressure/ temp.)
• Optional: external CO2 adapter/ quick connector."