I used these small shanks to install 2 flowcontrol taps to the tap tower. They come with a convex ring that lets you tighten it perfectly on the tap tower. They are short enough to easily fit into the tap tower, even 2 at the same height. It is also great that you can slightly angle the elbow pipe through defined notches before tightening the nut, to make the installation even easier. Great product.
These Duotigt products are simply great. These makes even cleaning so much easier.