If you own a fixed gear bike or have a Shimano Alfine Internal Geared Hub then you need a 15mm box wrench to remove the nuts on your bolt-off hub so you can repair a tire. Unfortunately, standard length 15mm box wrenches are too heavy to carry in your seat bag and the shorter cycling-specific wrenches usually hurt your hands when you try to use them. Surly, the maker of great bikes like the 1×1, Steamroller, Karate Monkey, and Pugsley, has a great 15mm offset box wrench for you—the Surly Jethro Tule.
The Surly Jethro Tule is made of highly polished stainless-steel and has a double-sided 15mm offset box wrench on one end with a bottle opener on the other. Sitting above the bottle opener is a spoon-shaped area that allows you to apply a lot more leverage than you can with traditional short wrenches. The offset design of the wrench makes it easy to reach inside recessed dropouts without fear of scraping your knuckles when the axle nuts loosen.
A large box wrench (like the ones you have in your garage) can apply a lot more torque than you will ever be able to get with the Jethro Tule. I would suggest you always use the Jethro Tule when installing or removing your wheels—that way you know you will be able to match the torque when you have to remove a tire the next time you get a flat.
The Jethro Tule does not have a carrying case, so to keep it from clanging with the other metal items in my saddle bag I just took a 5″ piece of an old inner tube and closed one end with tire patch cement. The Jethro Tule fits perfectly in this case and the seat bag stays quiet.
The Surly Jethro Tule retails for around $30 and if your local bike shop does not have it in stock they can order it for you. As mentioned above, the Jethro Tule has a bottle opener that some people love to use for a post-ride drink. That is kind of funny because I’ve never seen a carton of chocolate milk that needed a bottle opener!