If you have a Professional water blaster trigger and a Bosch water blaster and are trying to figure out how to connect them, this is probably what you need.

The inner components are aluminum and well built.  All the others we have seen and tested were plastic which does not last, these are quality.  Made by Rockcar.

The M14 thread threads onto the bottom of a water blaster upgrade trigger like the Rockcar Professional Trigger.  The bottom connection connects to the standard Bosch Series hose that connects into the normal Bosch standard gun.  It has a quick release, so you can pull the adapter up and it will pop off the hose, making it really easy to use.