The thread is not a 1 14" thread
In order to be able to suck out feces in the Netherlands, I bought the ROCA filler neck adapter WASTE and a reducer from 1 12" (ROCA adapter) to 1 14" (suction port 13583). I discovered that the diameter of the thread in the suction nozzle is approx. 1 mm smaller than the standard for 1 14". So the reducer cannot be screwed in. I will probably have to go to a turning shop to adjust the thread of the reducer I can't even think about what it's going to cost.