The Ultraflask 500ml is so light, you might forget you brought it. Weighing in at just over an ounce, it’s optimal hydration, no matter what kind of runner you are. Its pliable material conforms to most pockets, it shrinks as you drink to minimize water movement and it can be used with or without the tube. Ultra light weight, ultra useful.

• The UltraFlask 500 flask fits easily in most hydration vest, belt or pack pockets
• Soft material conforms to any pocket for a comfortable carrying experience
• Flexible design shrinks as you drink, reducing water movement on the run
• High-flow bite valve auto-seals after each sip, eliminating annoying drips
• Includes two cap sets: one with a removable bite valve mounted directly to the cap and one with an adjustable drink tube that can be cut to a custom length
• Large 42mm opening lets you fill the UltraFlask easily with ice and drink mixes
• Made of ultra-durable, abrasion resistant TPU & RF welded seams for superior durability and elasticity
• Can be frozen or filled with hot water (max temp 60° C / 140° F)
• Top-rack dishwasher safe
• Safe and reliable, 100% BPA & PVC free