A truly great sea run cutthroat and summer steelhead fly from the vice of the late great Harry Lemire out of Washington, hitch it and wake it, greaseline it, or swing it wet, or strip it. I do know from experience that not only steelhead but sea run cutthroat and rainbow trout will take this pattern with relish, especially in the spring/early summer when caddis abound. While it’s best fished from April to the end of November, you can definitely swing it year round. Don’t hesitate to use it beyond the banks of it’s namesake river. Harry Lemire created many good patterns, check out the greaseliner, steelhead sculpin and the fall caddis, amongst others.
Hook: size 10 to 2 Tiemco 7999 black steelhead/salmon hook or similar
Body: insect or caddis green to olive dubbing of your choice, other colours are worth experimenting with too, including brown, black, ginger, orange and others.
Rib: originally black tying thread, optional small gold oval tinsel, or nothing
Underwing: Natural green phase ringneck flank
Wing/head: Moose tied muddler style and sparse
If you look closely you can see the wing in the mouth of this summer steelhead
and a cutthroat from the same run
cutthroatsgalore 
Thanks for that one need to tie up a few. What is your go-to size for summers?
size 4 or 6 tiemco 7999 usually, nothing larger than that, and I’ve hit lots of fish on smaller versions