HydraPak Ultraflask + 500ml Filter Kit — 500 ml collapsible drinking flask with inline filter

The HydraPak Ultraflask + 500ml Filter Kit is a 500 ml collapsible drinking flask engineered for outdoor sports and endurance activities where lightweight, packable hydration and simple inline filtration are required. The soft, foldable body reduces bulk when empty, while the included inline filter improves basic water quality from natural sources. A secure screw cap and ergonomic nozzle provide controlled flow and reduce the risk of spills during running, cycling or fast-paced activity.

Advantages

The collapsible design saves space in a pack and allows the flask to be rolled or folded as it empties. The inline filter offers basic reduction of particulates and improves taste compared with untreated surface water. Constructed from flexible, BPA-free materials, the Ultraflask is lightweight and durable for repeated use. The secure cap and low-profile nozzle are designed to minimize leakage and make drinking on the move convenient and efficient.

Suitable for

• Trail running and ultrarunning where minimal weight and packability matter
• Day hiking and fastpacking with occasional access to natural water sources
• Cycling and commuting when a lightweight, stowable hydration option is needed
• Travel and outdoor day trips where compact storage and basic filtration are useful

Key specifications

• Capacity: 500 ml (collapsible when empty)
• Material: flexible, food-grade, BPA-free polymer
• Filtration: inline filter for particulate reduction and improved taste (basic filtration)
• Closure: secure screw cap with ergonomic drinking nozzle
• Weight: lightweight construction suitable for endurance use
• Packability: folds or rolls flat for compact storage

How to use

Open the screw cap and unfold the flask. Attach or verify the inline filter is correctly seated according to the included filter instructions. Fill the flask from a clean tap or an appropriate natural source, taking care to avoid disturbing sediment. Close the cap securely and use the nozzle to drink directly or to attach to compatible accessories if required. After use, rinse the flask and flush the filter with clean water; allow both to dry thoroughly before storing. Follow any specific maintenance steps supplied with the kit to preserve filter performance.

Usage recommendations

Use the inline filter for basic particulate and taste improvement; it is not a substitute for certified purification against viruses or all pathogens. For long-term storage, keep the flask dry and clean, replace the filter according to manufacturer guidance, and inspect seals and the nozzle for wear before each outing.