Ultrasonic, float or piezoresistive type level meters. Ultrasonic: quartz ultrasonic probe with measuring range up to 15 meters. Microprocessor electronic unit with pump control option. Maximum error 0.4%. Output 4-20mA. Float type: with stainless steel float, level indication on large dial. Option for transmission of signal 4 - 20mA. Piezoresistive type: piezoresistive level probe suitable for wells with extremely wide measuring range (over 250 m depth). Supplied complete with special cable with pressure compensation tube. Output4 - 20mA. Power supply 24 VDC.