New Design: For added comfort, Glacier Tek adult cooling packs now feature horizontal cells that conform to your torso as you bend and stretch. What's more: the packs come in two sizes: 10.3 ounces and 7 ounces. Set consists of 4 large packs and 4 small packs -- use only as many packs as you need to stay cool. For maximum cooling, insert a large and a small cooling pack into each inside pocket of your vest. For less demanding conditions, such as office use, you may lighten the vest by using a single large pack in each pocket. Fits all Original, Classic, Concealable and Sports cooling vests. Ideal for long rides on hot summer days, the packs are made with a proprietary high-tech, full barrier film that’s hermetically sealed for easy cleaning, disinfecting or sterilization and is completely odorless. Features: Glacier Tek adult cooling packs can be sanitized and recharged indefinitely. They are 100% biodegradable and contain no petroleum or harmful chemical ingredients. Ideal for home, office and light recreational use Features rounded corners for easy vest pocket loading and comfort Full barrier that is hermetically sealed for easy cleaning, disinfecting or sterilization Each set contains eight packs. The four large packs weigh 10.3 ounces each and measure 11.25" by 5.25" by 0.5". The four small packs weigh 7 ounces each and measure 8.75" by 5.25" by 0.5." Manufactured using the first PCM on the market that carries the USDA Certified BioPreferred label Completely biodegradable and leaves no harmful residue in the environment Contains no hazardous ingredients Made from 100% bio-based phase change materials Remains at a comfortably cool 59°F / 15°C when fully charged Recharges in as little as 20 minutes in ice and water, about an hour in the freezer or a few hours in the average refrigerator Can be sanitized and reused indefinitely (Glacier Tek cooling packs have been recharged 10,000 times in Glacier Tek's lab with no measurable change in performance) Made in the USA WARNING: Cancer and Reproductive Harm - www.p65warnings.ca.gov This warning is being provided to comply with the State of California's Proposition 65.