Temperature stability of up to -196°C (in vapor-phase liquid nitrogen). Quick seal closure and leak proof tube seal. Externally threaded without O-ring to avoid contamination. V bottom for maximum sample recovery. Auroclavable 121°C for 15 mins. Better stability with hepta foot for self standing and storage efficiency. Easy sample identification, Large and clear patch for personalized labeling. Certified DNase RNase and endotoxin-free.