Airsoft Atlanta got the Spartan Edition of the Wolverine Airsoft Reaper V2 HPA Engine in stock right now... "The Reaper is a new HPA airsoft system from Wolverine that features a true 'closed bolt' firing system. The air is locked and loaded for its first shot, ready to go. It's pretty much a hybrid combination of the Inferno and the BOLT (semi-auto) system wrapped up into a nice HPA package. The Reaper is not recommended for crazy fast ROF guns, as it's more for Milsim and other firing styles. Perfect for DMR rifle setups.

The Spartan edition is for M4 version 2 gearboxes only.

The Spartan programs itself with a slightly more tedious trigger firing programming.  FCU or battery not included.  The Wolverine battery or Valken 250 Mah battery will work just fine with it.  Fits in M4 airsoft AEGs."