28 x 28 - 3 Mil Flat Poly Bags - Sturdy Poly Bags are perfect for protecting medium to heavy weight products from dirt dust and moisture. 28 x 28 - 3 Mil Flat Poly Bags. Sturdy Poly Bags are perfect for protecting medium to heavy weight products from dirt dust and moisture. Bags are manufactured from 100% virgin high clarity polyethylene film. Meets FDA and USDA specifications. Close bags with Twist Ties Bag Tape or with Impulse Sealers. • Sturdy Poly Bags are perfect for protecting medium to heavy weight products from dirt dust and moisture. • Bags are manufactured from 100% virgin high clarity polyethylene film. • Meets FDA and USDA specifications. • Close bags with Twist Ties Bag Tape or with Impulse Sealers. • Sold as 250/Carton.