Automatic telephone switchboard.
Used by the US military since late 1970s until late 1980s. Designated SB-3614(V)/TT.
Used by the IDF during the Peace for Galilee War (1982) and the Security Zone Conflict (1982-2000).
The switchboard supported 30 subscribers. Three units could be combined to support 90 subscribers.
Each switchboard had three digits identifier, and dial plan was the switchboard identifier and subscriber number.
The switchboard was used with TL-427 and TL-428 telephones.
