This is a rare example of a super rare pre-WWII Japanese "Inagaki Shiki" semi automatic pistol. This is one of a few documented examples of this pistol currently known. It is estimated that maybe up to 500 were manufactured. However, only 6 surviving examples have been reported world wide and only 2 have the circled Navy acceptance proofs. This example and one other pistol (serial number 164). This pistol and the history of this rare model are discussed on 251-257 of the book Japanese Military Handguns by Derby/Brown. This design was submitted to the 1st Army technical research Institute in19411 and was put into production soon after that. It was approved for Japanese Naval pilots hence the Naval acceptance marks. The pistol is marked on the right side of the frame with Inagaki factory "S" with a line through it followed by two hand stamped Kanji characters followed by the Japanese circled Anchor proof mark. The serial number "160" is stamped on the left front side of the frame. It is fitted with an original set of acadia wood grips with the correct diagonal grooves. Both grip panels are numbered "95" on the back sides. It is complete with one original magazine numbered "37" on the underside of the baseplate.