Specifically manufactured cubes that fit between the breech face and hood of the barrel, for dry-fire practice.
Precisely determined width perfect for the distance the trigger on the P-10 need to travel to reset. Unlike other, less precise, methods, the trigger movement is perfectly repeatable from shot to shot and calibrated to realistic live-fire travel distances. No mushing of the trigger.
Because the cube only allows the trigger to move to the reset point there is a greater chance of improving trigger control.
Ideal for practising trigger speed or multiple shot drills in dry fire. It does not create a resetting trigger but rather is a sophisticated way of unlocking the gun enough that the trigger manipulates forwards and backwards without the striker falling.