Brüel & Kjær hydrophones are individually calibrated, waterborne‐sound transducers. Each hydrophone features a flat frequency response and are omnidirectional over a wide frequency range. In addition, their construction is s absolutely waterproof, corrosion resistant and can withstand high levels of salinity. If you are looking for high-quality hydrophones, usable at depths of 1000 meters, and with a build quality that can withstand static pressures of up to 100 bar - you've come to the right place.