For this product, please contact your Philips representative. The single patient use Nasal Alar Multi-Compatible SpO? Sensor* measures arterial oxygen saturation at the ala, which is an optimal measurement site for difficult-to-measure patients. It produces a strong, consistent signal, even in patients with poor perfusion¹. Designed for comfort and durability, the sensor is non-adhesive and can be used for up to seven days.