"Bulldog nose" is the nickname given, due to their appearance, to several diesel locomotives manufactured by GM-EMD and its licensees from 1939 to 1970. The term originated with EMD F-units, as well as later E-unit models such as the E7, E8, and E9. The bulldog nose design has been described as "iconic". It was a blunter and more vertical variation of the similar "slant nose" style, which featured a more sloped front and often less protruding headlight. Examples of this included the EMC E1.