Rexair LLC | 2,431 followers on LinkedIn. Since 1936, Rexair has developed and manufactured innovative products designed to improve indoor environments. | The World Headquarters of Rexair LLC is located in Troy, Michigan in the U.S.A. It is from here that the sales, marketing and independent worldwide distribution network of the Rainbow is coordinated and administered. The Rainbow Cleaning System has been the exclusive product of Rexair LLC for more than 85 years.