If it was me I would put them on a fly hook most likely, but if a Jig head is needed I would probably use a 1/64 head or you could probably go as big as a 1/32, but got to have not bigger than a #8 regular bend hook. If you don't have either I don't know what to tell you to do. However if they called it a Brim Killer the real thing is a fly and no hackle at all. Just rubber legs, floss, Peacock Herl and a bit of Squirrel.

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