OPST Junction Tubing is designed to be used with OPST steelhead and intruder shanks. To use OPST Junction tubing cut a piece 1/4" long. Thread you tippet through the top of the eye of the fly tied on OPST shank, bring the tippet along the underside of the fly, thread tubing onto tippet. Tie on OPST swing hook. Pull eye of hook into tubing, place other end of tubing over the end of the shank. Pull tippet tight to take out any slack.