The FS10A is a universal flow monitor and switch specifically designed for gas and liquid process analyzer sampling systems. The FS10A is a fast responding, highly repeatable sensor which installs easily into a standard tube tee fitting or new SP76 (NeSSI) modular manifold. The FS10A utilizes proven thermal dispersion flow measurement technology with FCI proprietary equal mass sensing to achieve outstanding sensitivity and repeatability. The instrument's wetted parts are superior corrosion-resistant 316L stainless steel with Hastelloy-C sensor tips. The sensor element has no moving parts to foul, clog or maintain which ensures continuous reliability and no maintenance costs. There are no cavities, orifices or dead-legs to trap or contaminate samples which preserves sample integrity and faster system sampling times. FS10A electronics are packaged in a rugged, fully-sealed, aluminum housing which provides exceptional protection and long-life under all process conditions. The electronics can be integral mounted with the sensor element resulting in unibody, self-contained unit (FS10A-N, FS10A-1, FS10A-2) or the electronics can be separated from the sensor for remote mounting (FS10A-, FS10A-3, FS10A-4). The remote configuration is useful when sensor installation area is subjected to high temperatures or to mount the front panel and display in a more convenient location. The instrument provides a top-mounted, flow rate monitoring LED array for at-a-glance visual indication of proper flow rate to the analyzer or sampling system, that an alarm/trip has been reached, and as indication the unit is powered and operating. The flow switch's setpoint is conveniently user settable via two push-buttons accessible at the top of the unit.