ROCKBROS Soft Flask 500 ml Light Blue - Collapsible TPU Hydration Bottle for Running

Weighing a mere 38 g, this ultralight soft flask delivers 500 ml of hydration without the bulk. Crafted from food-grade TPU, it's BPA-free and built to withstand the demands of running, cycling, and hiking.

Overview

The ROCKBROS Soft Flask 500 ml is a collapsible hydration bottle designed for athletes who value performance and convenience. Its high-flow bite valve and self-sealing design ensure leak-proof, on-the-go hydration, while the wide mouth makes filling and cleaning effortless. When empty, the flask folds down to a fraction of its size, fitting easily into pockets, vests, or packs.

What stands out

• Ultralight at only 38 g – barely noticeable during intense activity
• Food-grade TPU body and silicone mouthpiece – safe, durable, and taste-free
• Self-sealing bite valve prevents leaks and spills, even when inverted
• Collapsible design shrinks as you drink, reducing sloshing and saving space
• Wide temperature tolerance from -20°C to 50°C for all-season use

Technical details

• Capacity: 500 ml (0.5 L)
• Body material: Food-grade TPU (thermoplastic polyurethane)
• Mouthpiece material: Food-grade silicone
• Cap material: PP (polypropylene)
• Colour: Light blue
• BPA-free: Yes
• Leak-proof: Self-sealing bite valve
• Foldable/collapsible: Yes
• Mouthpiece type: High-flow bite valve
• Temperature range: -20°C to 50°C
• Opening type: Wide mouth
• Compatibility: Fits most hydration vests, belts, and packs
• Durability: Abrasion-resistant, tear-resistant
• Approximate weight (empty): 38 g
• Approximate dimensions (empty, flat): 250 mm (L) x 70 mm (W)
• Cleaning: Hand wash recommended, top-rack dishwasher safe

Our verdict

An essential piece of kit for any runner or outdoor enthusiast, the ROCKBROS Soft Flask combines featherlight design with rugged reliability, ensuring you stay hydrated without slowing down.