You are looking at an unused brass switch to disconnect a car battery  

Brass Battery Quick Disconnect / Shut Off Switch 

Clamps to top post of car automotive battery, negative side, and clamp cable from car, then rotate knob to stop battery discharge through car wiring.

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Please examine pictures for details as the posted pictures show the actual items you will receive after payment for very careful packing and shipping with cost calculated to your address from Holland MI.
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determine compatibility before purchase.
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Legacy Thrift Center
Holland MI 49423
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