Schneider Aventinus Keg Coupler/Tap (M System)
Recently introduced to the US market and sometimes called a tap, this is actually a coupler for Schneider and Aventinus kegs that features a slide-on keg connection and a stainless steel probe. This is the coupler only and it does not include a nut, nipple, washer, or beer dispenser.
Fits M system keg valves.
A non-complete list of breweries and beers that use the M system:
Schneider, Aventinus, Einbecker, Veltins