Guard samples against cross contamination, and laboratory work areas against infection and spillage with these universal snap caps. Precision-molded from low-density polyethylene and designed to fit firmly on the tube. Closures are very sturdy under most rigorous procedures, including centrifugation. Designed for easy-on and easy-off use. Cap removal is simple and quick. Universal caps are ideal for recapping most 12-mm, 13-mm and 16-mm evacuated glass blood-collection tubes. Flexible closures protect from aerosols of highly infectious microorganisms. Available in 8 colors for easy sample identification. Not suitable for autoclaving.