These premium quality borosilicate glass tubes provide excellent chemical resistance and durability. Dimensional specifications are rigidly controlled for reliable, uniform results. The tubes are produced in an ISO 9001:2008 certified factory. Tubes can be used for tissue culture and blood banks. Made from superior quality borosilicate glass to reduce pH changes and contaminants that are potentially leached from tubes made from soda lime glass. Tubes feature well-rounded bottoms and smooth fire-polished rims.