1. The semi-fluid cover plate is clear. The counterpart is vacuum-treated and isolated from ambient air and the measured water, making it resistant to damage and helping keep the pair secure. 2. Increase inner cavity and reduce pressure loss. As long as performance is maintained, enlarging the water inlet and outlet holes in the impeller housing can effectively reduce the water meter’s pressure loss. 3. Tamper-evident seals prevent water theft. Lead seals are applied after strict factory testing before shipment, indicating product qualification and preventing manipulation, thereby increasing security. 4. High standards ensure sensitive measurement. Accuracy to 0.0001, with a combined display of numbers and pointers. Applications and use scenarios - Domestic water metering in multi-unit buildings where tamper resistance and precise readings are required for fair billing and reliability. - Industrial process and cooling water systems where lowering pressure loss in the meter assembly improves overall system efficiency and reduces energy usage. - Municipal water distribution where tamper prevention and secure, verifiable metering are important for regulatory compliance and theft prevention.