| 摘要 |
A telephone subscriber's card index includes a flat casing having a top, side walls and a front opening, a tray adapted to be pushed into and pulled out of the casing through said opening, and a pile of index cards supported on the tray and intended to have information thereon. The index includes manually operable depressible keys, with dogs on the underside of the keys, for determining, before pulling out the tray, which index card is to be presented to an operator by depression of an optionally selected one of said keys.
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