Chin rest tool, aluminum
This little tool may be the best five dollars any violinist or violist will ever spend. Most pickups for acoustic violins have Carpenter-style output jacks, that mount on the side of your instrument with turnbuckles just like the hardware on your chin rest. This aluminum chin rest tool makes it dead easy to tighten or loosen that hardware, without risking damage to your violin's finish. You can even keep it on your keychain!