Scuba Choice Spearfishing Lionfish 6" Pole Spear Tip 3 Prong Head Paralyzer with Barbs Durable, Strong Stainless Steel materials Total length: 12" long Female thread: 8mm in diameter Thread diameter: 14.2mm, thread line: 1.25mm REPLACEMENT SPEAR HEAD ONLY FOR POLE SPEARS SOLD BY SCUBA-CHOICE