Knot, Sheet Bend

The sheet bend joins two lines, and is the correct knot when the lines differ in diameter or stiffness, where a reef knot would fail. The thicker line forms the bight; the thinner is rove through, around, and tucked under itself. A double sheet bend, taking a second turn, holds better in slippery synthetic rope or under intermittent load. The name comes from bending a sheet (a sail-control line) to the clew of a sail.