The shackle key is used to remove the bolt from shackles which are commonly found on sailing vessels to attach rigging. ... A shackle key (the open slit along the top edge of this knife) is used to open shackles commonly found on boats/sailing.

What is a shackle opener?

The shackle-opener (or shackle key) is used to open and tighten screw-pin shackles used on marine rigging. Available on some marine focused 111mm Victorinox knives, the shackle-opener is combined with a marlin spike, that is used to splice rope, untie knots, and other rope work.

What is a shackle in sailing?

Shackles are an extremely strong U-shaped piece of equipment that connects items together, securing with a pin, spring, or bolt. While most commonly thought of for industrial uses, shackles come in a variety of shapes and sizes and are used in boating to secure an anchor, hold lines in place, etc. Anchor/Bow shackle.