Solid rubber bands for your speargun = less hole = more rubber = more power, and no water intrusion into the band affecting performance and deteriorating the band from the inside.
Speardiver high performance %100 natural latex “no hole” rubber tubing for spearguns actually has a hole, it’s about the diameter of a pin. It’s somewhat difficult to insert knotted wishbones into this tiny hole. This rubber is really meant to be used with the Speardiver wishbone system http://www.freedivestore.com/speargun-rubber-bands/316-plastic-wishbone-inserts.html. These wishbones are fantastic and change band making into an easy process. All you do is drill an 11/32″ hole into any piece of wood, set the head of the plastic wishbone insert in the hole with the tapered stem sticking up, lubricate (with detergent) and stretch the hole in the rubber with a pointed tool, lubricate insert’s tapered stem and push the band over it. It takes 5 seconds and no wishbone insertion tool or pliers required.
Speardiver Spectra wishbone line http://www.freedivestore.com/speargun-rubber-bands/28-wishbone-line.html is ideal to use with the wishbone inserts. Insert the wishbone line through the hole in the head and out the side, with a lighter burn a glob on the end of the line and tie a single overhand knot. Do the same for the other end of the band, now pull hard on both ends of the band and the Spectra knot will settle into the hole and out of sight. The wishbone line can be easily pushed to expose the knot again and undo it, to thread the band through closed speargun muzzle holes.