Nelson the ballast tractor is very smart and his job is to deliver members of the construction team back and forth from work. He painted black with cream lining and has red alloy wheels with a front beam.
His name appears on his front cab right above his window and the number 10 appears oh his cab doors painted in cream.
He wears the number 10 on his side and is proud that he can haul heavy loads. Even though he feels overworked, he never complains about it.
Nelson is modeled after a Scammell ballast tractor with a low loader trailer. He has appeared in The Pack episode called On Site with Thomas, Thomas and the Moles, and Percy Helps Out.