internal thread 1.0 cm / 0.39 inch (M10)
|Outer Diameter (cm):||2.0 (0.8 inch)|
|Diameter of opening (cm):||1.0 (0.39 inch) M10|
With this coupling piece you can connect 3 pipes of 1.0 cm (M10) to each other.
The three holes make a T-connection (see the attached photos as an example).