What Not to Pack in Your Carry On Bag? liquids that weigh more than 3.4 ounces, sharp things like knives or scissors, flammable items like lighters or aerosols, and weapons or ammunition while packing your carry-on. Perishable goods should not be packed because they could spoil during the flight. To guarantee a trouble-free travel, don't forget to verify airline regulations twice. Make sure your travel goes well and keep your necessities close at reach.