Germany
A plug-in traffic light, at the lowest price in its family
TFA Dostmann appears in one family here: air quality monitors.
No setup, by design. Plug it into USB power and it reads immediately — no pairing, no app, no account, a genuinely different proposition from the Wi-Fi-dependent Airthings unit in this same family.
A traffic light without stated thresholds. The green/yellow/red LED changes with the CO2 reading, but TFA doesn’t publish the exact ppm values that trigger each color.
No stated sensor technology or accuracy tolerance. Unlike SwitchBot’s Meter Pro CO2, this listing doesn’t name an NDIR sensor or an accuracy figure — a real gap in an otherwise simple, capable device at its price.
0–3000 ppm CO2 · LED traffic-light · USB powered
A pocket-sized, USB-powered CO2 display with a three-color LED traffic light (green/yellow/red) and an alternating CO2/temperature readout. No app, no Bluetooth, no battery to replace — just a plug-in monitor for a single room.
Best for: A single room where someone wants a plain go/no-go ventilation cue — a bedroom, home office, or classroom — without setting up an app.
