JBL ProFlora CO2 Safe Stop (Safety Valve). The special water backflow stop ensures best protection for CO2 systems, pH controllers and solenoid valves. The installation in carried out by integrating the check valve with the arrow in direction to the aquarium (between diffuser and CO2 system). Recommended to combine with the T3 Connection Hose for best results.

• Protects devices such as CO₂ systems, pH control devices and solenoid valves against backflow of aquarium water.
• Mounting: cut CO₂ hose and mount in between the valve. For CO₂ hoses of 4/6 mm diameter.
• Arrow on the valve indicates CO₂ flow direction and thereby the mounting direction.
• Contents: 1 check valve with 2 hose lock nuts.