Gentex was founded in 1974 to produce smoke-detection equipment. The company sold its first glare-control interior mirror in 1982 and its first model using electrochromic technology in 1987. Automotive revenue is about 98% of total revenue. The company is constantly developing new applications for the technology to remain on top. Sales in 2023 totaled about $2.3 billion with 50.6 million mirrors shipped. The unit mix breaks out as 63% interior and 37% exterior, versus 31% exterior in 2019. The company is based in Zeeland, Michigan.