20 PCS 12" x 18" Heavy-Duty 4 Mil Reclosable Zip Bags. They were thickened to 4mil, and thicker than 2mil. So they are very strong and durable. [SPECIFICATION] : Heavy-Duty 20 Count 12" x 18" (below the zipper), The reclosable zip bags were thickened to 4mil.
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