Pack size of 10 plastic test tubes with White tops. 150mm (6 inch) long, 17mm outer diameter (Ø). Capacity is 20ml without cap fitted and 18ml with. These tubes can be used for any number of items, Fish food, Confetti, Bath salts, beads, Cigars and also as postal tubes for small delicate items, such as wedding invitations. Suitable for liquids.