handle hooks from about size 4 to size 4/0. Ideally, the vice will be “full rotary”, so that you can turn the fly upside down to work on it without removing it.
There are some beautifully engineered vices from $700 to over $1000. If you find yourself addicted to tying flies these great investments will last your lifetime and provide endless pleasure. However, a starter vice is a lot less eyewateringly-expensive, and the end products catch fish just as well.