this is the same thing the other company on here is selling but I'm cheaper The Ista Ultego III Heat Meter is a reliable and accurate device designed to measure the heat output of your home. With a 1" BSP qp of 6m3/hr, this unit is perfect for large homes with high heat demands. The meter is made from a durable combination of plastic and copper materials, ensuring long-lasting performance. This heat meter is a great addition to any home with a heating system. It is easy to instal and use, and will provide you with accurate readings for years to come. Whether you're looking to monitor your home's heat output or simply want to upgrade your heating system, the Ista Ultego III Heat Meter is the perfect choice.
eBay