The Ermes Fish Trick Caller can be placed on any wooden speargun, either on the right or the left of the handle. Being actuated by the thumb of the hand that holds the speargun, you can leave the other hand free (desirable state for easy hunting action).
The sound effect is made by a toothed wheel with a carbon fibre tongue. Turning the wheel generates a noise that stimulates the attention of many fish species. This sound is made even more effective by the structure which encloses the gear, which acts as a resonance box.
Small size and negligible weigh, the fish caller has 3 fixing points, one central with M4 screw provided with a hexagonal insert. suitable for wooden spearguns. Alternatively 2 side options would require a 3mm screw and nut - available separately.
It is up to the customer to decide exactly where to place it, depending on your preference.