Quick release hook, carabiner and plunger pin are all made of stainless steel, corrosion resistant in saltwater environment, less prone to rust, and hence, expect it to last longer. The marine sailboat shackles with swivel eye design allows the shackle to rotate freely 360°, facilitating smooth movement of ropes and chains in any direction, to prevent the rope from knotting, enhancing efficiency and safety. Quick release 316 stainless steel marine sailboat shackles are also used for boat, sailing, RV, backpacks, key rings, ropes, indoor and outdoor equipment,dog leash, kayak anchor system, DIY accessories. Quick release carabiner secures lines that need a quick release without accidentally releasing. Quick release shackle are perfect for an object that needs a quick release under tension, such as a sailboat rope system.