Wheel numbers

[Chas]

F: 19x8.5" ET44
Part#A2154010002/B66031022
R: 19x9.5" ET46
Part#A2154010302/B66031023

Can anyone tell me what the B numbers mean ?

 

[whitenemesis]

I believe the B numbers are referenced in the accessories catalogue

 

[Goodjob]

The 'A' numbers are the original part numbers for the wheels, the 'B' numbers are alternative part numbers. Whitenemesis is correct, most accessories have part numbers beginning with 'B'. For some reason Mercedes use the 'B' part numbers instead of the 'A' part numbers for replacement wheels.