This set is unusual in several ways, it has three different colored cars, but all are similar condition with the early 1910 characteristics. The box is unusual in that it Doesn't have the third line 'ELECTRIC and MECHANICAL usually found on 1910 boxes and later.  The cars are probably in great shape because they were ever if rarely removed from the original box - Note below - much like the Shroud of Turin - you can see the image of what was in box from the discoloration of the parts that weren't covered.

The side label is also unusual in that it looks like circa 1909, but has the word MECHANICAL printed on it.