A toolbox includes a space for receiving tools and includes a peripheral side and top and bottom sides. The peripheral side includes at least one snap fastener on an upper end thereof and at least one engagement portion on a lower end thereof. The at least one snap fastener includes a flexible engagement plate. A hook is formed on an upper end of the engagement plate. The lower end of the engagement plate can be pressed to move the hook away from the peripheral side of the toolbox. The hook of the at least one snap fastener of the toolbox can engage with at least one engagement portion of another similarly constructed toolbox stacked above the toolbox. The at least one engagement portion of the toolbox can engage with a hook of at least one snap fastener of another similarly constructed toolbox stacked below the toolbox.