I have rounded up several affordable large hiking backpacks that you could use for your 72-Hour Kits! I recommend LARGE backpacks for adult 72-Hour Kits because in the adult kits you will be packing the majority of your emergency supplies for your families. Small children will need much smaller and lighter backpacks than adults. All of these hiking packbacks are over 50L and under $40 LTKActive LTKHome LTKFindsUnder50