This is a rare example of what collectors have termed a Type 38 folding stock paratrooper carbine or a Type 1 Paratrooper. These were actually produced by the Nagoya Arsenal for a short time using the standard Type 38 carbine. It is theorized that the Nagoya Arsenal just pulled Type 38 carbines from completed production and modified them by installing this crude type, door-hinge mechanism at the wrist area of the stock. The design was very weak and fragile, and the stock usually split on the side or up the middle behind the receiver rendering the carbine useless. It was dropped from production after a few thousand were made, and they can generally be found in the 4000-5200 serial number range. The top of the chamber area has the royal chrysanthemum over the kana markings for Type 38. The side wall has the series five mark followed serial number and the Nagoya Arsenal stamp. It has a plum shaped bolt handle with the short staff, Type 38 rear sight and inverted "v" front sight. The hinge mechanism and buttplate are crudely stamped with "AA/40". The fore stock has the finger grooves on the sides with a full length handguard and a cupped buttplate.