Gaosen Kinetics does a quick review of the TTI Airsoft AAP01 Trigger which he says to be best upgrade for this popular gas blowback pistol... "Here's a quick review of the new TTI Airsoft Action Army AAP01 adjustable trigger, with a comparison to Action Army's own aftermarket trigger. This is a new product from a smaller company so I think many people aren't aware of it, but it's the best on the market as of now in my opinion."