The last time I bought a spoke key there was only one size (that I was aware of) and it probably cost me a pound or less. It worked on all my road bikes and mountain bikes at the time. Having just checked ebay, there appear to be about 6 or 8 different key sizes. Is that right? Is the single-size spoke nipple now out of fashion, and if so what key size should I be looking for? I like a tool to last a lifetime, and the only reason I'm buying a new one is my toolbox and bike got stolen along with the car.