Rob Allen Spinner Flasher, Any more effective for spearfishing and they would be illegal!
The advent of Flashers changed Bluewater hunting completely. Human visual capabilities are limited in the water and many Gamefish pass a spearfisherman by without being seen.
A well designed Flasher will stimulate a predator to change course and investigate it by reflecting light and emitting vibrations when in the water. This results in increased fish sightings as well as more shooting opportunities when they pause to look at the flasher.
Flashers should be deployed within visibility and shallow enough to allow any fish to be approached before they lose interest usually between 6m and 12m deep. The Spinner Teaser is the best choice in clear waters due to 360 degree flash effect while spinning.