Mercedes Benz Ponton Axle Bearing Clamping Lock Nut. 

Also used on the 220SE.

Includes the bolt.

Price is for one.

Ponton parts in my eBay store are divided into categories to make finding what you want easier.

I will combine shipping.

Most things ship the same or the next day.

International buyers please read:

It is the buyer's responsibility to pay all customs or import fees taxes and duties. 
I do not put false information on customs forms.