No one can find open the box? May be that is a Treasury Box! Can you open it? 
Measurment : 
Small -  10 (L) x 5(W) x 3(H)cm
Medium - 11cm(L) x 6.5cm(W) x 4.5cm(H)
Large - 15.5 (L) x 8.5(W) x 5.5(H)cm