Momentum is a minimalist design created by Eindhoven-based designer Studio Fabian Zeijler. Momentum is a series of aerometers that give off subtle warnings if you need to improve your indoor air quality. Instead of beeping or blinking, these devices start rotating silently when they detect high levels of particulates, low humidity or low oxygen. Abstract, poetic and tranquil, their appearance reveals what they are for: a pale blue drop to indicate water, a matte black disc for particulate matter and a white half sphere with a transparent top for ventilation.