With the rapid development of the Internet of Things, NB communication technology has gradually penetrated into all aspects of the gas meter, water meter and other industries. As for traditional large-diameter water meter, its structural space is limited, and it is impossible to expand on its existing structure. This wireless NB transmitter integrates NB IoT narrowband data transmission technology, and can connect any TTL module externally to send its data collection to the platform, making it possible to transform and upgrade the traditional large-diameter water meter. This product is designed with low power consumption, and the chip wakes up automatically. After reporting data, the chip automatically enters the sleep mode, saving energy; Large capacity lithium battery (+Farad capacitor) provides independent power without additional equipment and wiring. It is flexible in networking, regular reporting, remote control, and is not affected by communication distance; According to the actual use of the user, the report can be set every minute, hour and day through the network of the NB IoT platform. The reported data includes the cumulative water consumption, battery capacity, meter status and report period of the meter; Support online recharging and payment, and SMS message reminder.