VR2W is a single-channel the acoustic tags ultrasonic signal receiver. Usually the VR2W cloth on the river bottom or seabed formation of underwater monitoring network, when the fish through, you can capture the signal emitted by the acoustic tag. VR2W no one on duty 24 hours, belong to the "passive" type of practices. Mainly used for fish migration path, the survival rate assessment, the scope of activities, water distribution, predatory behavior, spawning / mating behavior, water pollution and underwater engineering thermocline effects on fish, fish, water next breeding research.