Use to connect braided leader butt to fly line with either permanent monofilament loop or braided loop connector; or to connect smaller end of braided leader butt to monofilament leader tippet with the loop in butt end.
There is a right way and a wrong way to connect loops. Below we describe the method for attaching the fly line loop to the leader butt loop; the same technique applies to attaching the braided leader butt to the monofilament leader tippet.
Pass the end of the fly line loop through the larger end of the leader butt loop.
Then pass the small end of the leader butt section through the fly line loop.
Tighten by pulling in opposite directions. You can disconnect the loops by pushing them toward each other and reversing the process. The correct loop-to-loop connection looks like a square knot when complete.
Incorrect loop-to-loop connection. Attaching the loops this way weakens the connection considerably.