Matsushita Metal Products (AKA National Denki) was a sub-contractor under the authority of the Kokura arsenal.
This particular bayonet is of the 88th series. Straight crossguard, blued, unfullered blade, flat bird's head pommel, rivets in the contoured wrap-around grips.
This series was the last series that included the Kokura (Tokyo) arsenal mark.
Note the Saka inspector stamp below the series and serial number.