The Pathos Sandvik shafts are heat treaded to reach 52 Rockwells. The stainless used has excellent mechanical properties. The Shark-fin shaft can be used on spear guns with open muzzle. All Pathos sharkfin shafts have the following characteristics: • Sharkfins have a classic shape and they are only 4mm tall allowing for high coefficient of penetration through the water. • Three sharkfins • Tri-cut tip • Low profile stainless steel flopper