In fact, now that you mention that is the piece, i recalled to have handled it before at the GO boutique here!
It's the B-uhr of GO am i correct ? That has a push botton at the 7 o'clock position, and when you push it down and hold it down, the central seconds hand stops, and when you release it then it moves again!
But alas, very unfortunately it's an automatic movement!
Thanks anyways!
Danke schone!
Stephen