This fly is one of the best nymph for fishing grayling using french style of nymphing.
For fishing trout I recommend to apply a layer of UV Resin from Deer Creek. In this way the body will be indestructible.
Materials:
Hooks: Maruto Dohitomi D82 BL size #16
Thread: 17/0 Uni Thread
Body: hand cleaned peacock quill -natural color
Tail: nutria guard hair -dark natural
Torax: mad rabbit dubbing in natural and yellow mixed
Legs: hen mottled barbs from Brahma hen
Back: cream and olive body thread from Devaux
happy tying 
Lucian