Met One Instruments manufactures weather stations and particulate monitors and samplers for ambient and indoor air. The BAM 1020 Beta Gauge is the only beta gauge manufactured in the USA with USEPA approvals. Approvals and certifications are also from Europe, Korea, Japan and China. Our service centers in Oregon and Texas are rated as one of the best in our industry. Established in 1985, MOI has been providing quality, reliable, user-friendly products around the world.