B+C Class

This type of arrester has the highest protection in case of a sudden overvoltage. Today this arrester is mostly used in boards, telecommunications, industrial and military centers.
Serge arrester Class B + C is used to protect the electrical systems at low voltage against lightning or switching electronic devices. The peculiarity of this type of surge arrester is that it won't get hot at the time of discharging ionized gas, so it's not necessary to keep it away from flammable items.