For most of products
Turn over the device so you can see a label on the back or bottom of the unit. Look for a character string next to the serial number, the looks like: “V: X.X”. This is the hardware version of the device.
For products without labels:
The number at the end of the FCC ID indicates the hardware version. If there is no version number, like V7TRX12P, after the model number, that means it’s version 1.
For products with management interface:
Open a web browser and enter the domain name which can vary between units in the address bar. The address for your device can be found on the label on the back or bottom of the unit.
Below are the official domains currently in use:
Router - //www.tendawifi.com
Range Extender - //re.tenda.cn
There is a character string “Ver:X.Y” (for example, Ver:1.0) in the Serial Number field, and the number X is the hardware version of the device. If the string is “Ver: 1.1”, normally it means that the hardware version is V1. Different model has different management interface.