How about using these cardboard boxes for mail-delivery, perfect for using up points or trying out? ・Click Post ・Yu-Packet ・Yu-Mail ・Standard Mail (Teikeigai) These are the right size for the above! *Please note that the sizes are quite specific, so be sure to check if they fit the size you usually use! *Each box is folded by hand, so there may be slight wrinkles or misalignments in the folds! Please refrain from purchasing if you are looking for a perfect product! Outer Dimensions (Assembled) 333mm x 236mm x 29mm *Outer dimensions are calculated dimensions. Slight errors may occur due to the way the box is assembled, warping, or manufacturing dimensional tolerances.