They used to have winter (W) additive and Summer (S) additive, the stuff in the small soft plastic bottles.
They then switched (about 5 or so years ago) to a single product I believe is called VR9422 (not sure about the 9422) which is summer and winter use. You're supposed to use it with straight water in the summer, or "domestically available" washer anti-freeze in the winter. I think all it is is detergent to help keep the blades clean. MB used to put a few of these in the trunk of the new cars, not lately that I am aware of. So you can use whatever washer solvent you like with an appropriate freezing point, I like the yellow colored Prestone washer solvent. One of those small bottles of VR 9422(?) treats about a gallon or two of washer solvent/anti-freeze.
Just ask in the parts dept about the washer solvent additive, it's all MB sells now, they do NOT sell the solvent/anti-freeze itself, just the small tubes of additive!

Gilly