Abstract: A tool box includes a base, a plate and a cover which is pivotally engaged to the base, the base has four side walls and a bottom from which a plurality of studs extending therefrom, each stud having a hole defined in a top thereof, the base having two opposite side walls each having a groove defined in an inner side thereof, the plate having a plurality of recesses defined therein and having a plurality of pin elements extending downwardly from an under side thereof for engagement with the holes of the studs, the plate having an extending portion extending from a side corresponding to the groove of the base so as to be received in the corresponding groove.