I'm figuring it's a c-class with the single wiper?

Mercedes used to sell a simple rubber blade in which you removed the old wiper blade then took apart the two thin metal stripe that inserted along it length and replaced them into the new rubber blade with the notches facing outward. You then slid the new rubber blade with the metal inserts into the wiper arm blade holder from the bottom, and pulled it threw until it set into the notches. THAT IS WHAT THE DIAGRAM IN THE OWNERS MANUAL TRIES TO DUPLICATE.

Now Mercedes (maybe even BOSCH) sells a whole wiper blade attachment that means you simple Press SAFETY TAB DOWN push wiper blade downward to remove (as described in the manual) and just reverse the order with the new blade.

If you took a few pictures and posted them we could confirm.