12-Pack Glass Test Tubes with Natural Cork Stoppers, 25mL, 18 x 150mm, Borosilicate Glass

This pack of 12 borosilicate glass test tubes comes fitted with size #6 natural cork bark stoppers. Each tube has a 25mL capacity and measures 150mm (5.9") long and 18mm (0.7") in diameter, with a uniform 1.2mm wall thickness. The industrial-quality borosilicate 3.3 glass can withstand direct flame, high temperatures, and thermal shocks. The premium cork stoppers measure 24mm in length, with a 13mm bottom diameter and a 19mm top diameter. The corks provide a tight fit while remaining easy to insert and remove. These tubes are designed for professional laboratory use but are also well suited for storing liquids, powders, seeds, beads, and other small items.