Employing micropower impulse radar, Detector Series MIR-800 measures any liquid with dielectric equal to or greater than 3. Sensor outputs 4-20 mA level reading with resolution and repeatability of 0.01 in., and with response time less than 2 sec. Trimmed to any length, stock 24 and 72 in. models measure to within 1 mm of tank bottom while maintaining top deadband of 1/4 in. Extended-length Series MIR-900 handles depths to 12 ft.