These one-use culture tubes are packaged for your convenience in easy-to-open, easy-to-use packs. The three small sizes come in a dispenser arrangement, and the larger sizes are bulk-packed. Made of borosilicate glass to reduce pH changes and contaminants potentially leached from soda-lime glass. These one-use culture tubes are packaged for your convenience in easy-to-open, easy-to-use packs. The three small sizes come in a dispenser arrangement, and the larger sizes are bulk-packed. Made of borosilicate glass to reduce pH changes and contaminants potentially leached from soda-lime glass.