Does the HALO require calibration?

Yes, the HALO does require calibration. However, it does remember the last calibration.

HALO electrodes are considered to be SMART electrodes. All of the calibration data is stored on the electrode itself instead of the meter. This means that even though the electrode still requires calibration, it will remember the last calibration and hold that calibration even if unplugged from the meter. It will also give you a reminder to calibrate if the calibration is too old.