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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 offer the same core features as the AV-04FD and AV-04SD, delivering high-quality video and clear sound transmission to indoor monitors. Additionally, these versions are equipped with is the inclusion of built-in inductive loops, enhancing which greatly improve sound transmission for users with hearing impairments, while retaining all the functionality of the previous versions.
Call button backlight statuses
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