Works on octalink and square tapered cranks. Allows for unlimited leverage with a wrench or crescent wrench, with the added benefit of ergonomics of the handle. Not intuitive at first but the roller at one end comes off and goes on to the other end to convert it from splined to square tapered crank compatibility. Why buy two tools when you could just buy one? It also takes up less room.
Ride enough, and sooner or later, your derailleur hanger will become misaligned. And when it does, shifting suffers. You could take your bike to the shop and pay a mechanic $35+ to realign it, or you can pick up this tool and do it yourself in a matter of minutes. It's simple to use, and Park Tool has a great You Tube video that shows you how to do it right. Two realignments and the tool has paid for itself. Like all Park Tools, this alignment gauge is well made and will last. It's a solid investment for anyone who enjoys working on their own bikes
There's not much to say about this item. As can be seen in the pic, it's a solid piece of metal with six tools along the edges. Does an effective job at basic roadside repairs, although you won't have every size allen bolt you need, particularly if you're on the road with your kids and their bikes along with your own. Also the length of the item can get in the way of screwing or unscrewing a bolt - meaning you might only be able to turn the bolt 20 degrees at a time. That being said it's a quality, reliable, simple tool and I expect it will last a lifetime.
