The HydraPak Flux 1L Ultra-Light Reusable Bottle stands upright like a hard bottle and packs down to pocket size when empty. It's up to 50% lighter than traditional hard bottles and is designed for comfortable carrying. The Twist to Drink Nozzle performs like a traditional wide-mouth bottle but with more flow and less splash. Quickly open and close the drinking nozzle with one hand without any direct contact with dirty hands. A dual-layer film laminate adds structure, and the abrasion-resistant TPU and RF welded seams provide superior durability and elasticity. The bottle can be frozen and works effectively with temperatures under 140°.