favor of single-letter designators. The letters H, K, and V can be seen on the rollsigns of some older model subway cars, with colors paired to the last primary trunk line they were assigned to. The letters P, T, U, X and Y could last be seen on R32 side rollsigns as a black letter inside a white circle. See also New York City Subway nomenclature List of New York City Subway lines List of New York City Subway services List of New York City Subway stations References