Airsoftjunkiez have put together a KRYTAC FN Herstal P90 HPA Package for those looking for an HPA-powered P90. This uses the Wolverine Hydra P90 HPA Engine and tank regulator options are thte Redline Mini-SFR, PolarSta MRS, Wolverine Storm orr hte Airsoftjunkies SLP regulator which requires an SLP tank.