"Courtesy", "Secured Memory", and "Hotline" phones used in hospital lobbies (for taxi service), airport directories, building entrances, office reception area...

Viking K-1500 Hotline

Deka 1100-14 Secured Memory

Deka 1100-18 Customer Service

Deka 1100-13 Courtesy

Deka 1100-13 Hotline

Please also see:

Payphones

Elevator phone

Emergency phone

Bombproof & Hazardous Area phone