12x75mm Glass Test Tube, with 12mm Rubber Stopper, Black (Pack 10) Karter Scientific 401X2;

Karter Scientific is a registered trademark in United States of America. To maintain quality control, authorized permission is required in the resale of our products. These reusable glass round bottom Test Tubes are made of 3.3 borosilicate glass to reduce pH changes and contaminants potentially leached from soda-lime glass. Rubber Stoppers are made out of excellent grade rubber featuring low sulfur content. Do not use stoppers with food or drink.