Danfoss AB-QM 4.0 Flexo (003Z1633) — a DN 20 pressure-independent balancing and control valve (PICV) for the terminal branches of heating and cooling systems. A built-in differential-pressure controller keeps the flow through the settable orifice constant regardless of pressure fluctuations elsewhere in the network; the presetting dial fixes the maximum flow and the valve also shuts off. Connection Internal thread. Supplied without strainer. Left-hand version. Supplied with test plugs for commissioning flow/pressure measurement. standard flow range, nominal flow 1.1 m³/h. Pressure class PN 25, media temperature -10 °C to 95 °C (media). OEM designation "AB-QM 4.0 Flexo 80 DN 20 wo strainer". OEM P/N 003Z1633. EAN 5702424604783. Contains lead per the REACH candidate list. Technical data quoted verbatim from store.danfoss.com (code 003Z1633).