The ALD Holder is open on both sides of the sensor to prevent uneven pressure changes over the two sensor faces, hence enabling measurements at both low and high ambient pressures. Cables are provided to connect the ALD Holder to the measurement chamber. The measurement signal is transferred via two separate cables through the chamber wall to the QCM-D electronics unit. The ALD holder is suited for the electronics unit of the QSense Explorer, but is also compatible with the electronics unit of the QSense Analyzer and the QSense Pro.