Aristocraft Wheels

[Gibbster]

Could someone please tell me the difference, if any, between Aristocraft Wheels 29111B and 29111D.  I have been looking for some wheels and found some B's but I have usually purchased D's. 

Thanks in Advance for your help.

[EMD Trainman]

Gibbster

Could someone please tell me the difference, if any, between Aristocraft Wheels 29111B and 29111D.  I have been looking for some wheels and found some B's but I have usually purchased D's. 

Thanks in Advance for your help.

Aristocraft 29111B wheels are black in color and the 29111D are silver.