... It's a basic "Trigger Shoe". Common with Target Revolvers, and I've even seen them on the "Match" 303s . Works well in that it spreads the finger pressure over a larger area, creating the illusion of a lighter trigger. Good for single action,Target Revolvers, BUT not so much for double action revolver shooting. ( Hard to achieve consistent trigger finger placement, and potentially, safety issues on re holstering. ) If drawing the Revolver, and firing from a holster, 'definitely slows things down a bit. ..... David K