Metal detector ideal for search in salt and fresh water, as well as on land and the beach. Has two frequency 5 kHz and 15 kHz, Fisher CZ 21-10 Metal detector is ideal for search in salt and fresh water, as well as on land and the beach, Special underwater metal detectors and detectors-amphibians, It is a specialized metal detectors designed to find containing metal, Interference from fresh and salt water mixed and detection depth depends on the environment, Beach search with a metal detector. loss of depth detection of work in both salt water and fresh, It is an underwater metal detectors allow scuba divers to find Beach Search brings considerable dividends in water easily.