THE BASIC PRINCIPLES OF FORCED RESET TRIGGER

Also any one know somebody that does awesome engraving that could make me a 3rd situation marking over a Aero M4E1 lower to match the Safe and sound and hearth markings style it's? Or an honest vinyl sticker that will go there if all else fails.I'd an thought to get a trigger which was a loop and can be neutral in the middle, but hearth when pushed