Our Siemens Products range can be operated under maximum 150 degree C temperature range and 12v to 80v voltage range. This type of range consists of piezo electric crystals inside it. These crystals are instrumental in vibrating its fork in standard frequency level in the air. The vibration tends to decrease gradually when this switch is submerged in liquid. Reduction of vibration occurs due to density of fluid. Electronic circuit of our Siemens Products range is used to determine frequency change of vibration to identify presence of fluid.