The Rayovac Keychain Battery Tester is a convenient and compact device designed specifically for testing hearing aid batteries. This item is new , never used with no box. With a battery storage compartment and an LCD display, this single item accessory allows you to easily check the battery level of your hearing aids on-the-go. The keychain design makes it easy to carry around and access whenever needed, perfect for ensuring that your hearing aids are always in good working condition.
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