Picture yourself in the cosmetic aisle at your favorite store. On the right, are jars containing nail polish remover. On the left, smaller jars of powder foundation. Though the two items are packaged differently, all jars are inherently the same, right? Wrong.Plastic jars are molded in a few variations. Knowledge of jar basics will make finding your ideal packaging a smooth process. Read on to cultivate and master the art of jar selection, if you can handle that much brain power.Double-wall jars are made from two pieces of plastic. Hidden inside the outer shell of the jar is an innerwall, leaving a hollow space. This gives the illusion that the jar is bigger than it actually is. Michelle might choose your 4 oz double-wall product over a competitor’s product of the same size in a single-wall because your jar looks bigger. Cha-ching.We carry double-wall jars in white, frosted, black intermittent fasting diet and natural colors. The jars have rounded or straight bases, ranging in capacity from oz to 8 oz. We also stock low profile options, perfect for cosmetic applications.Single-wall jars are made from one continuous piece of plastic. These jars are manufactured in a variety of styles. The Oval has a shoulder and straight sides, the Tuscany is characterized by narrow shoulders, bulging center and a tapered base.Our single-wall jar sizes range from 1/8 oz to 32 oz, in various colors. Most are made from PET, but we supply options in both HDPE and eco-friendly Post consumer resin (see our post about this innovativeplastic) as well.Heavy wall jars are assembled from a single piece of plastic, like single-wall jars, only made from moreresin, resulting in a thicker look. We stock these jars in clear and amber, from oz to 4 oz. A heavy wall is the quintessential spice jar.Knowledge is power.