Hawaiian slings are not polespears. They consist of a steel spear shaft, a barrel that serves as the guide for the spear shaft, and rubber tubing that is attached on each side of the barrel. The tubing also needs a metal cap at the opposite end, which is used to hold the shaft in place. Hawaiian slings are almost like underwater slingshots that shoot a spear. The distance the shaft travels is dependant on your strength; the amount of strength you have to pull back on the rubber tubing. Using a Hawaiian sling accurately takes a lot of practice and skill.
Cost: $40 to $100