I mean to get one of those next time I get near an IKEA. Here at least, it costs less¹ than the sensor inside it.² (Of course, IKEA purchases more than one…)

¹ https://www.ikea.com/ca/en/p/alpstuga-air-quality-sensor-sma...

² https://www.digikey.ca/en/products/detail/sensirion-ag/SEN63...