Trb5p
(Trb5p)
9
Greetings from Istanbul, welcome to BLF 
I have an Opus BT-C3100. Several times inserting wrong side of 18650 cells didn’t made any harm to my beloved Opus. I used to be pretty sure that it has a polarity protection. Since the C3100 and C100 fundamentally the same charger, I will be more cautious for the battery polarity from now on.
By the way, I am very proud of you guys what you doing in TAI. I am a great fan of ANKA :+1:
Cheers