P403 KUMON, it has "Pull-Bolt-Release-system".

The shape of the holding hooks seem like one of the hiragana that is the japanese-character and is pronounced "KU".

The name KUMON (KU + MONJI) means "KU of the hirabgana".
And it also has a meaning of the "9 Gates" in Japanese.

The way of loading confuses the shooter a little.
First, you need to pull the Sliding-Bolt backward. And load the rubber bands from the holding-hooks to mazzle-hook.

And next, the Sliding-Bolt must be closed.

Last, pulling the Charging-Piece.

The Charging-Piece.

9 rounds.

The Sliding-Bolt.

The straight frame panel.

The grip design.

The mazzle-hook.

The right side view.

The left side view.

Made from japanese tilia plywood, cypress and ramin. The materials of the grip are keyaki (japanese zelkova).

It must be called "Pull-Bolt-Open-Release-System" or "Gate-Open-Release-System".

Please watch Video.

YouTube video