Callbox

A call box or callbox is a (usually metal) box containing a special-purpose direct line telephone or other telecommunications device, which has been used by various industries and institutions as a way for employees or clients at a remote location to contact a central dispatch office.

Some taxi companies used callboxes before the introduction of two-way radio dispatching, as a way for drivers to report to the dispatch office and receive customer requests for service. Taxi callboxes would be located at taxi stands, where taxis would queue for trips.

Also before the introduction of two-way radios, some police agencies installed callboxes or "police boxes" at street locations as a way for beat officers to report to their dispatch office. Before the development of emergency telephone numbers and the proliferation of mobile phones, some firefighting agencies installed callboxes at various street locations, so that a pedestrian or driver spotting a fire could quickly report it.

A growing number of retailers use call boxes in their stores as a way for shoppers to summon service (Shopper Call Box) as well as for store employees to summon assistance (Director Call Box). Retail call boxes are generally wireless devices that communicate to in-store communication devices via radio frequency (303 MHz) or through 802.11 networks.

Call boxes also exist at regular intervals along the sides of many highways and rapid transit lines around the world, where drivers or passengers can use them to contact a control centre in case of an accident or other emergency. Such call boxes are often marked by a blue strobe light which flashes briefly every few seconds. Boxes in remote areas often now have solar cells to power them.

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Wikipedia