New Cosmos sold 75 million gas alarms across Asia before most Americans knew the category existed. Now its Chicago-area outpost is quietly wiring the U.S. for a hazard no smoke detector was ever built to catch.
Honeywell spun it off in 2018 as an afterthought. Six years and three acquisitions later, Resideo is a $6.76 billion home-safety business splitting itself in two - and betting the boring stuff on your wall is worth more apart than together.