Qorpak GLC-01708 Clear Glass 16oz Straight Sided Tall Jar, with 63-400 Black Polypropylene Cap and PTFE Disc (Case of 12) Ready to clean bottles are designed for users who prefer to use their own cleaning process Ready to clean bottles are fully assembled with polypropylene caps and a friction fit 0.015" PTFE disc Both cap and liner can be washed, heated or autoclaved depending upon your application The PTFE disc is chemically inert, and will not interfere with your test results Measures 69mm OD by 169mm height