The Hosiden Besson line powered loud extension tonecaller, based on the No. 3 Line Jack unit is designed for internal use in domestic or business premises. The Teletone is neat, compact and unobtrusive and can be wall or desk mounted.

The Teletone extension tonecaller is ideal for use in open plan offices where four different sounds on the switchable version enable the user to distinguish their phone ringing in a busy working environment. When used in the home, Teletone is an unobtrusive, pleasing extension tonecaller that can assist persons with hearing difficulties to detect the phone ringing.