Pakistan Air Force (ensign, 1947-Present)
September 7 is Air Force Day in Pakistan. The Pakistani air force ensign is based on the Royal Air Force Ensign. While the British ensign has a 1:2 ratio, this ensign has the same 2:3 as the flag of Pakistan. The Indian Air Force Ensign, on the other hand, maintains that 1:2 ratio and as a result it has an elongated flag in the canton.
The circular device in the lower right corner is Pakistan’s roundel. Wikipedia has a nice gallery of roundels on their site, and it’s worth perusing if you’re interested in flags.