This is one of my oldest pattern and also one of the most succesful for me. For years I tied only in large sizes and used it for the hatching of the Ephemera Danica or Vulgata hatching here in Sweden, then after I had showed it to Dennis Shaw he went and tied a much smaller version of it and since then I too tie it smaller also these days. There is a Step by step published here:

http://elmerfishing.com/en/bindbeskrivn ... iller.html

It says poly yarn in the material listing, but I tend to use TMC aero wing much more often. Also these two photos below has a little to many turns of hackle for both, you really don't need that many turns since it is so light.

The original with the wood duck feather body:


The smaller one with a patridge feather body: