The monument 1515u water flow weir gauge is a professional water flow measuring device designed for plumbing and heating system installations. This essential diagnostic tool enables plumbers and heating engineers to accurately assess water flow rates before installing appliances such as washing machines, boilers, and shower systems, ensuring adequate flow is available for optimal performance. Constructed from durable plastic, the gauge incorporates a stainless steel mesh strainer that prevents turbulence during measurement, delivering reliable and consistent readings. The dual scale display measures flow rates from 2 to 25 litres per minute and 1 to 5 gallons per minute, providing flexibility for different measurement preferences. This water flow gauge is particularly valuable for diagnosing performance issues with existing installations. When a combi boiler or water heater is underperforming, measuring the water flow can quickly identify whether limescale build up is restricting flow and indicate whether de scaling is required, helping to restore system efficiency. Features and benefits bull dual scale measurement display for convenience litres and gallons per minute bull stainless steel mesh strainer prevents turbulence for accurate readings bull suitable for pre installation testing and diagnostic work bull durable plastic construction for long term professional use specifications tool type flow tester