To reset a device to factory default:
This resets the device to original factory defaults, meaning that devices that came in a home pack, will still be meshed with each other after a reset, while any additional access points must be re-added to the mesh after a reset.
Note that for a mesh network to be reset, you must reset all devices within 1 minute and 30 seconds.
See also Extending your AirTies mesh network with an additional device.