The
A Division, also known as the
IRT Division, is a division of the
New York City Subway, consisting of the lines operated with services designated by numbers (
1,
2,
3,
4,
5,
6,
7) and the
42nd Street Shuttle. These lines and services were operated by the
Interborough Rapid Transit Company before the 1940 city takeover. A Division cars are narrower, shorter, and lighter than those of the
B Division, measuring .