This item is part of the ShieldPro 1-Gallon Specialty line. It includes a 4" gusset at the bottom of the bag, allowing it to stand up for easy filling of long term storage food. It is made of the trademarked ShieldPro 5 Mil Extreme material for the best moisture, oxygen and light proteciton for your food. A 1-Gallon bag will hold around 5-7 pounds of dry goods. Most customers can use a standard household clothes iron (on about the wool setting) to seal ShieldPro bags, but folks storing large quantities of food may want to look at our KF-150CST heat sealer for the absolute easiest method of sealing.