To provide a bookbag making a user feel light in weight applied on the shoulders or entire body to a level of one severalth or more of the weight, compared with a conventional bookbag having shoulder straps each secured and further adjusted in length between a pin portion and a pin hole, even when both of the bookbags have the same weight level.
The bookbag has a slidable adjuster mechanism for adjusting the length of a shoulder strap and securing the shoulder strap, and the slidable adjuster mechanism includes an upper or lower shoulder strap having a locking projection formed in a width direction of the strap, and a lower or upper shoulder strap having a plurality of recessed grooves formed at predetermined intervals in a width direction of the shoulder strap and locking the locking projection therein.
KIMURA HITOSHI
Takayoshi in the daytime
Shinichi Ogawa
Takashi Noguchi
Kenji Sato
Isao Hirai
Masao Sakaizawa
Kazuhiko Saishita