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R / Restore of appliance: The switch is switched to the right →. Used to load the clean system image from an SD card. Read instructions at “Restore of appliance (for VT335i, VT825i, VT855i, VT960i & VT960ii series and VT855t series)”.
2. "LTE slot modem" - "VT740 / LTE slot modem" can be installed in this slot. This modem is ordered separately. Read instructions at "VT740 / LTE slot modem", and "LAN, GSM, LTE, RADIUS, DNS, SSL, VPN".
3. "SD card" - MicroSD card slot with an ejector. The card is needed for data storage or the "system restore" and saving logs. Read instructions at "Saving system logs to SD card", and "Restore of the appliance (for VT960 series)".
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9. "DRY CONTACT INPUTS 1...8" - Digital Dry contact inputs (Type IN). Pitch 3.5mm, 6P. Read the instructions at "Connecting dry contacts", and "Dry contacts settings".
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