Boat Marine Clip Blue Aluminum Safety Spring Hook Carabiner 8cm, 3pc Pack Heavy-duty bolt snaps are designed for saltwater use Premium-grade quick links for chain/rope,cable connections; threaded-nut closure for added security This link allows you to attach two chains or cables without cutting An easy-open threaded nut allows you to safety unlock and close (Height 0.2" x Length 3" x Width 1.6")