I doubt tarpon on the feed are going to be too particular about the fly pattern but the general profile should suggest what they are after and it should be tied on a hook that has a chance of holding them (see recent thread).
If it were me I would tie black cockroaches for tradition, black page's bigeye baitfish, black deceivers, large shrimp patterns, half and halfs, etc on high-end hooks like the Tiemco tarpon hook and/or the Gami tarpon hooks.
Good luck and hold on tight!
BTW - where are you located and what type of situation are you fishing... a lighted dock? Lagoon? Channel? Beach?
Are you fishing from shore?
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