Article storage case

An article storage case comprising a substantially cubic or rectangular parallelepiped form having an opening oriented upwardly,

• wherein a sidewall of the article storage case has an outside surface formed with an engagement projection and an engagement recess, the engagement projection is configured to movably fit into the engagement recess of another one of the article storage case, the engagement recess is configured to receive the engagement projection of the another one of the article storage case, and when a plurality of the article storage cases are placed side by side, the engagement projections and the engagement recesses of adjacent storage cases engage each other,
• wherein the engagement projection includes a projecting ridge extending horizontally from the outside surface of the sidewall, the projecting ridge having a vertical cross-section that is substantially T-shaped, a base end of the T-shaped projecting ridge being attached to the sidewall, and a front end of the T-shaped projecting ridge including bulged tips that respectively extend upwardly and downwardly,
• wherein the engagement recess is an elongated recess extending horizontally on the outside surface of the sidewall, the engagement recess having a vertical cross-section that is substantially C-shaped, a closed side of the C-shaped engagement recess being combined with the sidewall, and an open side of the C-shaped engagement recess having a front opening that is narrower than a cross-sectional area inside the C-shaped engagement recess, and
• wherein an overall height and size of the front end of the T-shaped projecting ridge is smaller than a height and size of the front opening of the C-shaped engagement recess, and the front end of the T-shaped projecting ridge freely passing through the front opening of the C-shaped engagement and an inside the C-shaped, when the front end of the T-shaped projecting ridge and the front opening of the C-shaped engagement recess are horizontally aligned.