The Jyarz portable jar is an innovative container for storing your stuff. It has an outer plastic screw-top container, made of high density polyethylene (HDPE). The HDPE container has latex rubber inserts in the lid and bottom. The latex rubber in the lid functions as a seal. A glass cylinder fits precisely inside the HDPE container. When the lid is tight, the latex rubber tightens against top and bottom of the glass, creating an airtight seal. An airtight seal is not formed unless the glass cylinder is present. The inner diameter of the glass cylinder is 1.03 inches (26mm); Inner length of the glass cylinder is 2.52 inches (64mm). Glass cylinder wall thickness is about 0.060 inches (1.5mm). Outer dimensions of the jar are 3.2 inches long and 1.43 inches diameter at widest part. Glass cylinder is well-protected from shocks and breakage. At VG, we believe this is a high quality product!