The Nakajima Ki-27 “Nate” was a successful low-wing monoplane, all metal fighter design used by the Empire of Japan throughout World War II. Conceived of as a private venture design by the Nakajima Corporation, the Ki-27 was soon debuted and accepted by the Japanese Army. It was the equivalent of the Navy A5M.
If I recall correctly, when Hasegawa first produced this kit it was Kit # 001, so that leads me to believe the Ki-27 was the first 1/48 kit produced by Hasegawa. I could be wrong so don’t quote me on it.