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The Birzman Damselfly chain tool is a great choice for the average cyclist who is willing to spend more for a higher quality product. It's very comfortable, durable, and fits most chains, but it's about 3 times as expensive as a quality budget option.
Specs
Pros
Pro Very comfortable to use
This chain tool has a wide, wing shaped handle that feels very comfortable in your hands, and it's easy to turn when pushing pins in and out of the chain links. The Birzman Damselfly is the only chain tool with a handle design like this, and it would be appreciated by those who break chains often.
Pro Fits most chains
The Damselfly can be used with BMX, single-speed, 9, 10 and 11-speed chains, as well as older 6, 7 and 8-speed chains. The only chain it won't fit is 11-speed Campagnolo, which requires peening. This versatility is achieved by having a spring-loaded chain guide, which can be adjusted to the thickness of your chain's plates.
Cons
Con Too expensive if you're not going to use it daily
For a tool that most cyclists will use about once a year, it's definitely too expensive. However, if you're someone who likes their tools to be as comfortable as possible, and if you don't plan on working on Campagnolo parts, you might consider getting the Damselfly Universal.