VXI46.25T 3-port zone valve, internally threaded, PN16, DN25, kvs 5, kvs bypass 5. 3-port valves, internally threaded connections, for the control of zones or terminal units. Suitable media: water (to VDI 2035), water with anti-freeze.1) 100% kvs in bypass, low leakage in bypass 0,05% of kvs value.