● Made of medical grade polypropylene; can be repeatedly frozen and thawed
● Multiple threads for super sealing performance
● Thickened tube wall (explosion-proof) and cap for safe sample storage
● External thread vials’ caps lack o-rings, which reduces the possibility of contamination
● Black graduation printing and white writing area
● DNase & RNase free, endotoxin-free, foreign DNA free
● Gamma radiation sterilized; autoclavable