Here you all go. Thomas's Best Friend, Percy!
Percy is the No. 6 green engine. He is the junior member of Sir Topham Hatt’s railway. He is quite content puffing around the yard with no particular desire for adventure in the world outside. Percy is Thomas’ best friend and his favorite job is delivering the mail. He is always happy to help and other engines sometimes take advantage of his good nature. Percy is an 0-4-0 saddle tank engine based on engines from the Avonside Engine Company.
For those that want to know 0-4-0 means: zero wheels in the front, 4 wheels in the middle, and zero wheels in the back.
It's amazing, at first you think they are all alike, but when you get down to the details, there are so many differences.