Features: 1) Functions: a) Used chiefly for underwater acoustic measurement in seas, rivers, lakes, ponds and pools b) Astatism c) Sending and receiving all-in-one d) High output 2) Material: seawater resistant stainless steel 3) Specifications: a) Cable (m): 15 (lengthened cable available) b) Weight (kg): 1.5 (including cable) c) Height (cm): 20 d) Omni-directional response e) Octave bandwidth (optional) f) Efficient transmitter g) Broad band operation h) High power projector i) Deep water capability