Surgeon's Knots can be used for different types of materials and one of the most common things this knot is used for is fishing line. It is used most often for fishing for two reasons, first, it is an easy knot to remember and tie. Secondly, the Surgeons Knot is strong and estimated to be up to 100 percent strength as if it were a continuous line. This is a knot that can be used to join different materials whether equal or unequal in diameter but with the strength as if it was one piece without separate ends.
There is also a Triple Surgeons Knot, which works on the same principle as a plain Surgeon's Knot. The way this type of single knot is tied is by making two overhand knots and pulling the entire leader through the knot each time. The Triple Surgeon's Knot is done by wrapping three times through the loop of the overhand knot. This kind of knot because it is a triple can be large because of the number of lines. the excess after the knot is tied can be trimmed.
To ensure the knot is tied properly and is 100 percent strong and the way it becomes this way is after the knot is tied it must be tightened. The knot is tightened by pulling on all four strands or if doing a triple all the strands. This will seat the knot and then the excess after the knot is seated can be trimmed.