Danfoss AB-QM and MSV-S set, DN 20 — a pre-paired terminal-unit assembly combining an AB-QM pressure-independent balancing and control valve on one side of the coil with an MSV-S manual shut-off/drain valve on the other, giving flow control, isolation and drain-down in a single ordered kit. The AB-QM holds design flow independent of network pressure while the MSV-S allows the terminal to be isolated and drained for service. Without test plugs. OEM P/N 003Z1243. EAN 5710104030524. Technical data quoted verbatim from store.danfoss.com (code 003Z1243).