Cressi gun pump:
Cressi gun pump for Pneumatic spearguns is used to pump the pressure in the barrel. For optimum performance of a speargun that maybe lacking in punch. Please note it is not necessary to pump the gun after every use. You can damage the inner workings of the gun by over pressurising the barrel. So only when you notice a lack in the pressure then give it a couple of pumps.
Tip for Pneumatic Spearguns:
NEVER fire the gun out of the water. They are designed specifically for in water use, you can cause great damage to the inside of the gun which can be very costly. And please NEVER load the gun out of the water before you dive in as accidents can and have happened never rely on the safety.