The Double Sheetbend is a more secure form of the Sheetbend.

         The thicker rope of the two is used to form a bight, and the thinner rope is passed up
         through the bight, around the back of the bight, around again before tucking under itself.
         Tip. It is particularly useful when the thickness of the two ropes varies considerably, or
         when a more secure Sheetbend is required.