As a watchmaker I know that this tool is terrible. It is large, unwieldy and the end bits are brittle and poorly finished. They will either snap off or scratch the watch. If used incorrectly you can damage the shoulders of the watch and this comes with no instructions on how to use it most effectively. The gauge may look useful but you won't use it on a regular basis. This may seem like a simple, inexpensive little hand tool, but it is more trouble than it is worth and you'd be better off spending a little more on a more refined tool if you wish to regularly swap straps at home.
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