Total 6 Compartment, 6 Compartments are all the same size of 5.5 x 5.5 x 5cm / 2.2" x 2.2" x 2" (L*W*H). You can remove the some blocks between two compartments to form a longer compartment. A ring on one side ensures you can hook the case to somewhere. Can be used for storing resistors, small screws, nuts, washers and Lock washers, keys, paper clip, etc.