415B KTUs--Auto Tie Line

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These Western Electric 415B KTUs can be used in your 1A2 Key System. They work in the same card slots as the 400-type KTUs. Normally, you would have one 415B at each of two KSU locations, and a single pair to connect the two locations. Signaling is automatic when the line key is pushed and the telephone goes off-hook. At the called station, you can have either interrupted ringing or steady ring, along with the flashing lamp.

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$8.99 each with free shipping!