Milestone av technologies plays a supporting role to the big screen. the firm develops and markets an array of audiovisual and display equipment (such as projector and display mounts), a/v furniture, and accessories. it serves more than 4,500 clients, including consumer electronics retailers and home theater dealers (such as best buy, abt electronics). milestone markets its products under the chief, raxxess, and sanus brands, among others. the company operates sales offices in the us, the netherlands, hong kong, and china. founded in 2004 by the merger of sanus systems and chief manufacturing, milestone is owned by investment firm duchossois group. in 2011 milestone acquired screen maker da-lite screen.