Kashi Sceintific cryogenic tubes are made of medical grade polypropylene [PP] and is endotoxin-free. They are disposable laboratory consumables dedicated to storing biological samples. The anti-slip lines on the cap and the tube body are easy for screw. 
Free from DNA, RNase, RNase and endotoxin. Sterilized by gamma irradiation.
Built-in O-ring to prevent liquid leakage
The cryogenic tube can be stored in the gas phase liquid nitrogen and can withstand low temperature to -196 °C