The Mark V (5), also known as the Suitcase Armor is an Emergency Suit, and was the fifth Iron Man suit built and created by Tony Stark, sometime between the events of the Iron Man and Iron Man 2 movies.
It was featured in the movie Iron Man 2, and made it's debut in the movie when Ivan Vanko terrorized the Grand Monaco Racing Track, and tried to sabotage and kill Tony, for the disgrace that his father, Howard Stark did to his family.
The suit was built as a base for experimenting on newer and better transport features for Tony's suits, so as he would be able to don them faster than before. It specializes in smoother transport, and it is collapsed into a suitcase and can be deployed anywhere, allowing Tony access to the suit especially in a civillian environment.