Uses: The Surgeon’s Loop is essentially a Double Overhand Knot. It can be tied quickly and easily in the end of a line. It is often used to make a “Loop to Loop” connection in the same way that two elastic bands can be hooked into each other. It can also create a fixed loop that allows the artificial lure or fly to move naturally.
Tying it: The Surgeon’s Loop is tied in the same way as the Surgeon’s Join Knot.
Alternative: An extra turn can be used to create a Triple Surgeon’s Knot. However, this provides minimal additional benefit and makes the knot bulkier.
Advantages: The advantage of the Surgeon’s Loop is that is reliable, easy to learn, and some sources claim that it retains a high proportion of the rated line strength.