Minigrip Reclosable Bags 2 mil w/White Block 9X12X002WO 1000Ctn #3975 ITEM NO / SKU Minigrip created the zipper closure. The signature red line across the top of the bags identifies this as the best reclosable bag in the industry. Features large white writing area that accepts either marker or pen. These tough bags employ a reinforced side-welded zipper to lock in single smooth motion. Made of 100% virgin Low Density Polyethylene (LDPE) resin that meets FDA/USDA specifications.