Our range of extremely popular 1/2" and 3/4" (also known as 15mm and 20mm) BSP threaded brass hot water meters are rated to 90 degrees C and 16 Bar maximum operating pressure. Popular with or without a reed switch pulse output, these Italian made hot water meters have mutliple overseas approvals. These meters should preferably be installed horizontally with the dial facing upwards, however, if necessary they can be installed vertically but the water flow must be upwards.