What is this thing soldered between battery leads on flipsky 6.6 mini?

[iNoLikeFlexyDecks]

Shitty DIY and nothing else!

[received_2696130404032600] [received_172260784654132] Its legit All electronics are housed inside the suitcase. 10s7p Lingy esc running sensorless And ownboard (hobbywing) hubs Mudflaps were added. This is my most waterproof build.