The Claber 91209 End Line Drippers have an adjustable flow rate between 0 to 6 litres per hour. The drippers can be installed into a 1/2-Inch (13-16mm) main tube or 1/4-Inch (4-6mm) feeding tube. Super simple to install and easy to clean.Claber End Line DrippersMPN 91209EAN 8000625992..