Partridge Bartleet Traditional Salmon Fly CS10/1 hook.

The name describes the effect of the blue tinsel body. Unfortunately the photo picks up too much reflection to show the true blue color.

Black dubbing, black spey hackle, Lagartun tinsel ribbing, and a teal collar all covered by a traditional style bronze mallard wing provide a dark silhouette to entice steelhead.

There is "something" about blue on a fly - "something" that makes it work.

This pattern comes counter-ribbed (not shown in picture).