TDK B72205S421K101 S05K420 Disk varistor 680 V 1 pc(s)

Varistors are voltage dependent resistors with symmetrical U/I characteristic curve, the resistance values of which drop as the voltage increases, thus 'short circuiting' any further build up of overvoltage. Varistors protect against all types of overvoltage and prevent damage to electronic equipment.

Price: £ 0.23 from Conrad Electronic