Valve that keeps the flow rate constant during operation within a certain differential pressure range thanks to a membrane device with a contrast spring. Complete with two pockets G 1/4"F for piezometric sockets (IVAR AVB 10) and with plugs for piezometric sockets and cartridge. PICV 00 (female) connections: G 1/2"F, G 3/4"F, G 1"F in compliance with ISO 228/1. PICV 05 (male - flat seal) connections: G 3/4"M, EUROK, G 1"M, G 1"1/4M in compliance with ISO 228/1. PICV 10 (with unions) connections: G 1/2"M, G 3/4"M, G 1"M in compliance with ISO 228/1 and EN 10226-1. To combine with PICC 01, PICC 02 or PICC 03 cartridges. PICC connection: M32x1.5. Compatible with water or glycol solutions max 30%. Min operating temperature: -20 °C. Max operating temperature: 120 °C. Max operating pressure: 25 bar. Max closing pressure with PICC 03: 6 bar. Valve material: CW617N brass. Sealing gaskets material: Peroxide EPDM. IVAR PICC 01: 8 flow rate ranges to set; brass and POM insert; HNBR/Peroxide EPDM diaphragm; Peroxide EPDM sealing gaskets. IVAR PICC 02: 41 flow rate ranges to set even during operation; brass and PSU insert; HNBR/Peroxide EPDM diaphragm; Peroxide EPDM sealing gaskets. IVAR PICC 03: 41 flow rate ranges to set even during operation; to combine with IVAR TE 3003 electrothermal actuator (M30x1.5; ON/OFF 230 V AC or ON/OFF 24 V AC or proportional 0-10 V 24 V AC adjustment) or IVAR RV 03 axial motor (M30x1.5; 2 points/3 points 230 V AC or 2 points/3 points 24 V AC or proportional 0-10 V 24 V AC adjustment); max closing pressure 6 bar; brass and PSU/POM/PPS (glass-fibre reinforced) insert; stainless steel internal metal components; PPS/Peroxide EPDM cone; HNBR/Peroxide EPDM diaphragm; Peroxide EPDM sealing gaskets.