Fly Fishing Knots: Loop-Loop Connection Video
The Loop-Loop Connection is used to attach a loop leader to the permanent loop on the end of a fly line.
How to Tie the Loop-Loop Connection
2. Pass the end of the leader through the loop on the end of the fly line.
3. Pull the line and the leader away from each other, until the loops slide together to form what looks like a square knot. You may have to help the knots pass through the loops with your fingers.