recipe:

hook: 6-12 streamer or standard nymph hook, depends on how large youd like to go. weighted

thread: brown 210 denier

thorax: brown rabit zonker wrapped forward to eye of hook.

add two piece of crystal flash or tinsel and youve got yourself an awesome lake leech and great for stripping accross riffles. change color to suit to leeches in your area and go with a flesh color if you live where salmon are hatching