All RA-UN/UR valve bodies can be used together with all types of thermostatic elements in the RA 2000 series. The valve bodies are fitted with a kv limiting device for pre-setting of max. water flow. RA-UN is for mounting in the flow and RA-UR in the return. An arrow on the valve body indicates the direction of flow. The valve body RA-UN/RA-UR is used in two-pipe heating systems and is available with the following setting ranges for max. water flow: RA-UN kv = 0.02 - 0.48 m³/h RA-UR kv = 0.02 - 0.47 m³/h The valve bodies are supplied with a protective cap and adjusting screw which can be used for manual regulation during the construction phase.RA-UN valve bodies can be used with all types of thermostatic sensors with gas-filled below type Danfoss Aveo®, Aero®; liquid-filled below type Danfoss React™, Redia®, Regus® and with thermal actuators type TWA..