This is the Ocean Hunter D Shackle 20mm for Spearfishing Features: 20mm Stainless steel multipurpose D-shackle for various rigging configurations The Ocean Hunter D Shackle 20mm has been manufactured from marine grade stainless steel for superior rust prevention and to ensure a long working life. This multipurpose D shackle can be used for various rigging configurations and will provide an ideal connection point for securely connecting your float line swivel to your float. The Ocean Hunter D Shackle can also be used to provides a secure attaching point for a shark clip to the handle of your speargun.