Hook bend dropper knot
 

When using rings you may also ignore the "diameter drop rule" for
tying knots in fishing line. This rule states that for many knots a
difference in nylon ( or whatever), diameter of more than few thou,
renders the knot unreliable.

As this does not apply to jam knots on rings, you can use any tippet
you like. This has a number of considerable advantages.

TL
MC

Hook bend dropper knot
 

More knot info;

http://marinews.com/fishing_line/lea...hing_line.html

http://www.letsflyfish.com/knots.htm

http://www.bigfishtackle.com/Resourc..._fly_knots.htm

TL
MC