The 16mm Click Fit Adapter and Filter is designed to be used with all sizes of FlexiTank and FlexiTank Pro. It is simply pushed onto the tap provided. It has a 16mm filter incorporated along its length to filter the water before it travels along the pipes. This fitting allows the user to push 16mm pipe, (Hosepipe) onto the end of the adapter.
 
Specifications
The external diameter of the fittings is 16mm, the internal diameter is 13mm, so any pipe marked with 13mm diameter will work fine. For the side with 9mm external diameter (7mm internal diameter) it's only available the Autopot 9 mm Pipe, this will assure no leaks in your grow room!