The Bently Nevada 991 Thrust Transmitter is a 2-wire, loop-powered device that measures shaft axial position and delivers a proportional 4 to 20 mA output signal. Designed for smaller, non-critical machinery such as centrifugal air compressors with fluid-film thrust bearings, it accurately monitors up to 1.2 mm (50 mils) of thrust movement for reliable machinery protection and control system integration.