45 Caps are available in many different materials, sizes, styles, colors, and liners. For more information on Wheaton closures and tips on liner selection, see our Technical Data section. For example, a size 28-430 cap has a diameter of 28 mm, and fits a container with a 430 GPI thread finish. At left is a selection of caps and finishes. These autoclavable caps for use with biological media, volatile solvents, corrosive chemicals, and sensitive compounds.
Closures consists of a liner ultrasonically welded into a polypropylene cap.
The use of a low compression set silicone is ideal for the storage of samples and sensitive materials for prolonged periods of time, over wide temperature ranges. Teflon or polypropylene film on the exposed face of the liner imparts an inert, highly chemical resistant surface ideal for the containment and storage of volatile solvents, sensitive compounds and corrosive chemicals.