United Scientific™ Culture Tubes, Disposable, With Screw-Cap Finish, Over Flow Volume 20 ml

Manufactured from 5.1 expansion borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class B requirements, these threaded culture tubes are suitable for a variety of lab settings. Each tube is heat-treated at temperatures exceeding 500° C and immediately packed in a shrink-wrapped cardboard tray, 250 tubes per tray. This process avoids contamination and increases the strength and durability of the glass. Dimensional tolerances are strictly controlled for a uniform shape, including rounded bottoms and polished tops with smooth edges. Each tube has a chevron-shaped white enamel marking spot. Threaded necks accept a phenolic screw cap, not included. Available in six sizes, from 8 mL to 33 mL. (1000 per PK )