It is a re-settable circuit breaker. If it trips you have to remove the source of power clear the short or overcurrent situation and it will reset when power is restored. They cost about $5 and I recommend carrying as spare. Be sure to get the same amperage breaker as what you have. They also will corrode easily so a coating of Vaseline will help protect it.
As well as corrosion protection, periodically check the tightness of the connections... Mine came loose and fried the breaker. You can get them at any auto parts store.
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2014 Jayflight Swift 264BH
2015 Ford F150 XLT 4x4 SCrew 3.5 EcoBoost Max Tow
Equalizer 10K
Linear Mode
