What Is The Triple Crown? The US Triple Crown is the premier point series for indoor R/C Racing on carpet. The series dates back to the 1980's and usually spans from October-March of each year. There are five classes of competition to choose from: 1/12th 4-cell Stock 1/12th 4-cell Modified 1/12th 4-cell Masters 1/10th 6-cell Stock Sedan 1/10th 6-cell Modified Sedan The series consists of five races of which your best three finishes count towards the series points total.