Resealable plastic bags are the most common type of cigar case because most tobacconists use them to package individual cigars.  Often referred to as ziptop, Ziploc (registered trademark), or zip bags, these products will retain moisture for well over a week in most cases.  These bags can be placed in a drawer, or any place with relatively little air movement to prolong the optimal condition of your cigars.  Over time though, humidity will seep through the bag’s seal into the drier ambient air.  A tiny humidifier or small piece of damp sponge can be added to supplement humidity if necessary.  Since these bags are free to consumers, their cost to benefit relationship is extraordinary:  perhaps the best value cigar case available.