Electrical products which have LCD time counter, Layer sensor, Three-phase AC fault protection relay and so on.

其中电器类产品有液晶显示计时计数器、平层感应器、断相错相三相交流保护继电器等等。

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The units, dubbed "Churchill's Secret Army", were set up to relay vital information about enemy movements and help mount counter-attacks as Britain braced itself for occupation.

BBC: Secret wartime bunker near Cardiff opened to public