T-knot loop is good for creating attachment points for leaders on the main line. Thanks to tightly wound bushings on all three arms of the knot, the knot is quite strong and does not weaken the attachment point as much as other loop knots. In addition, the side leash on such a knot, due to the bushing, extends at a right angle from the fishing line and is less tangled. This is complete video instructions on how to tie T-knot for creating leash connection points on fishing line - full step by step how to video tutorial.