"While most dry fly hooks are what is called 'standard length'. Nymph hooks can be standard or 1x long, 2x long and on up, or even 1x short, 2x short on down. What the number before the 'x' means, is they are actually 1 hooks size longer or shorter shank than standard. For example a size 14 1x long nymph hook, is actually the same hook length as a standard size 12. Every tier and fly supplier has their own preferences, so a size 14 Hare's Ear, might actually be tied on a 1x long hook or a 2x long hooks, thereby appearing like a larger fly to the fly angler."
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A Primer on Fly Tying Hooks by Cameron Larsen@ Rodfishing.net