Difference between S.M. 500 and S.M. Brown

Can anyone describe the difference between these two snuffs. S.M. Brown is said to be Menthol and Eucalyptus while S.M. 500 is said to be Chinese Menthol and Eucalyptus . Is there much of a difference if at all? I have S.M. Blue which is Menthol and Camphor and I can tell the difference between that and the Brown but what about the Brown and 500?

More of a complex menthol in the 500 or at least that is my opinion.