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The main difference between devices is the type of installation. AV-04FD is a panel with flush-mounting installation, and AV-04SD requires wall-mounting installation.
The distinguishing feature of the AV-04FDI and AV-04SDI models is the addition of an interface for connecting an inductive loop, which greatly improves sound transmission for users with hearing impairments, while retaining all the functionality of the previous versions.
Call button backlight statuses
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