These pouches are 4¼" x 7½" x 3" on the outer measurements. Inner measurements are 3¾" x 6" x 2½". (LxHxW) They are made of aluminum foil and multi-layered polyethylene. These are suitable to store items that have a sensitivity to oxygen and/or moisture. They have a tear-off notch above the zipper. Can be resealed by heat or the zipper. Also compatible with vacuum sealers.