2010 A8 A/C low side port need adapter
 

Wow, Audi did a number with this. The A/C low-side port is a metric male thread with a 1.5 thread pitch. It measures 12 mm in diameter with 0.5 mm thread depth.
I cannot find an adapter so as to connect a quick-connect fitting to add some R134a refrigerant. Any help regarding this would be appreciated.