These boxes are used to dispose of empty ampoules, broken glass, empty vials, biohazard wastes, etc. The outer box is made from corrugated cardboard; the inner one is a 2-mil polypropylene bag. When the box is full, the safety cap is pulled into place and the entire unit is ready for disposal or incineration. There are no replacement bags for these boxes. Meaures:12"(L) x 12"(W) x 20"(H), opens: 7"