I just ordered my first single speed in about 20 years and it will not have quick release skewers/hubs as I've grown used to. That's cool. But, then I thought about fixing flats on the trail and wasn't sure what type of wrench to use. I know (if I remember correctly from my BMX days) that it should be a 9/16th, but I can't imagine lugging around a couple of box wrenches in my Camelback. I checked Nashbar and didn't see a wheel-specific wrench for this purpose. What do you guys use/recommend?