The hard reset button manually disrupts the power connection with the battery on the power meter housing. The zero offset will not be affected by a hard reset.

To perform a hard reset on the Gen 3. Stages indoor power meter (971-0103): Push the hard reset button, located at the end of the power meter housing. Upon hard reset, the power meter will reboot and resume broadcast.

Note: If you have a Gen. 1 / Gen. 2 Stages indoor power meter, 971-0100 / 971-0101, it will not have a hard reset button.
Please see the related article: How to hard reset the Stages power meter (971-0100 & 971-0101).