MADE IN THE USA!!! At HammerHead Spearguns we are proud to say our spear shafts are made from the finest quality American sourced Stainless Steel and heat-treated to perfection right right here in the USA. Manufactured from 17-4 PH Stainless Steel and heat-treated for perfection HammerHead Evolution shafts are Ultra-straight, ultra-hard shafts and have heavy duty welded fins and Hawaiian style floppers or threaded ends. Designed to fit into American style mechanisms such as Alexander, Neptonic, Riffe, and Wong. American Square-Cut shafts are available in a variety of diameters including 9/32" (7.1 mm), 19/64" (7.45 mm), and 5/16" (7.93mm) diameters shafts having 2, 3, or any multiple of fin tabs. As HammerHead Spearguns manufactures all of our shafts in-house right here in the USA customizations such as multiple fins, loading tabs, double floppers, welded floppers, 6 mm threads, 5/16" threads, high luster polishing, etc. are no problem.