Both the PurpleAir Flex and the PurpleAir Zen have two PM6003 laser counters, to ensure confidence in the data reported. They also contain a microSD card logger and a real-time clock to allow for local recording of data.
Both sensors feature a BME688 from Bosch that measures the temperature, humidity, and pressure of the device. Volatile organic compounds (VOCs) are also measured, however, the VOC readings from our devices are currently experimental.
They both feature mounting brackets that can be easily removed, and the laser counters are built into a quick-release system, making them easy to access. Both devices can be used both indoors and outdoors.
The Flex also includes a full-color LED that shines out of the underside of the device. This LED will glow the color associated with the current air quality (green, yellow, orange, red, purple, maroon).
The Zen also offers the following features to increase ease of use:
A double-tap feature to adjust LED brightness
A new, transparent casing, and an LED ring all around the device instead of the single LED on the Flex
A detachable base mount, which allows you to swap between an outdoor mounting bracket and an indoor stand
The Flex and the Zen are both capable sensors. So which one is right for you will depend on what ease of use features you would like, and what your desired user experience is.