surge protector device Product DescriptionCAN-D20 series surge protection device (in short: SPD, alias: surge suppressor, surge arrester) is suitable for TN-S, TN-C-S, TT, IT ... .Application Scope and Installation PositionIt's suitable for D grade (class) lightning protection, CAN-D20 series surge protection device according to IEC61643-1, GB18802 ...