Shock Leader Knot
This is a strong knot suitable for attaching a heavy shock leader in fly casting or surf casting. It is also excellent for attaching a heavy leader to superbraid, although in this case the superbraid should first be doubled using either a thirty turn Bimini twist or a twenty turn Spider hitch. The braid loop should then be wrapped for 10-12 turns around the leader rather than the six turns illustrated.
For extra security an Overhand knot can be tied in the end of the lighter line before snugging up tight.