Traditionally the Buntline Hitch was used for attaching buntlines to the eyes or eyelet holes in square sails, which came into use when it was time to pull in a reef.
Triangular sails and jiffy reefing put an end to their traditional use but today they're used for attaching lines to hardware such as shackles and carabiners.
A high-strength secure knot, the Buntline Hitch can be used as an alternative to the Anchor Bend.
Insert the working end of the line through the eye of an object, in this case a Carabiner Snap Lock Hook, from back to front;
Now take the working end and make a full turn around the standing part of the line, working away from the eye;
Pass the working end from back to front through the loop formed next to the eye;
Pass the working end under its own working part which will lock it in place when pulled up tight;
Finally, tighten the knot by pulling on bothe the working end and standing part.
You've tied the Buntline Hitch!