7724: Electrical apparatus for elec. circuits >1000volts

77241: Fuses, voltage > 1000 volts 77242: Automatic circuit breakers for a voltage < 72, 5 kv 77243: Other automatic circuit breakers, voltage > 1000 v 77244: Isolating switches, make-and-break switches, >1000 v 77245: Lightning arresters, voltage limiters, surge suppre. 77249: Other apparatus for electrical circuits>1000 volts 7724: Electrical apparatus for elec. circuits >1000volts