Heavy duty mailing box w330 x d370 x h152mm p10 heavy duty mailing box 370x330x152mm pack of 10 7373401 heavy duty mailing box w330 x d370 x h152mm made from strong corrugated board this mailing box can withstand the toughest of journeys the quick and easy fastfold pop up design allows for almost instant use the strong adhesive self seal strip creates a secure closure to keep contents safe during transit and a simple tear strip allows for easy access when it arrives at its destination p