| JBL Competition Magnum 450 Spearshaft |  | | The 756 S Shafts are all made of 3/8 inch diameter hardened spring stainless steel and is 56 inches in length. Replacement shaft for the JBL Competition Magnum 450. | |  | |  | | JBL Shaft 4D49 Speargun |  | | The 742-S Shafts are all made of 5/16 inch diameter hardened spring stainless steel and is 42 inches in length. Replacement shaft for the JBL 4D49 speargun. | |