This is our high efficiency valve for the Benjamin Marauder. By doing nothing other than installing this valve and using the factory hammer spring, and hammer spring adjustment, we can dial a shot string up to well over 900fps, and/or it can increase your shot count per air charge. This is probably the best single modification for your Marauder. These valves require very little force to open, and the best initial
setup is to utilize our twin spring setup and remove the larger spring, and the back the tension way off such
that the hammer free-flights during firing. If you don't have a twin spring setup (TSS), then back your stock spring adjuster all the way back. It's possible (though we've never actually done it), that firing the valve with a heavy hammer, and a heavy hammer spring, with no pressure in the tank, could cause damage to the valve internals. Please refrain from using heavy hammers with this valve.