A speargun scaled down for underwater hunting it is a speargun that uses a gearing mechanism for increase the power of the blow and the speed of the shaft. In practice, the demultiplied speargun is equipped with a pulley system which transforms the force exerted by the operator into a greater force, allowing more energy to be stored in the system. When the operator pulls the trigger, the pulley system releases stored energy, accelerating the rod and increasing its power.
the system in question allows to considerably reduce the recoil effect of the speargun, as the rubbers of the mechanism move in the opposite direction with respect to the rod at the moment of the shot. This entails a significant reduction in the pullback force, thus increasing its effectiveness and comfort of use.