HydraPak
HydraPak SkyFlask Speed 350 mL Handheld Soft Flask
- Weight for its size: 7/10 How much it adds to your pack for the water it holds.
- Packed size (empty): 8/10 How much room it takes up when it is empty, for the water it holds.
Lowest price we found
£26.99 at Ultralight Outdoor Gear
Go to Ultralight Outdoor Gear Compare 2 shopsRunning or fast walking with a bottle in the hand rather than in a pocket
- Type
- Soft
- Capacity
- 0.35 L
- Weight
- 60 g
- Packed
- Not published
Where to buy
Ultralight Outdoor Gear £26.99 In stock. Free delivery. Shop shows RRP £28.49. Its page lists 60 g and 350 mL, 20.3 x 7.1 cm.
View at shop: Ultralight Outdoor GearHydraPak £28.50 In stock. Delivery £3.60. HydraPak's UK shop. Free UK delivery over £50 on its shipping page (£75 on its shipping policy page); under that it is £3.60 by Royal Mail Tracked 48 or £6.00 by DPD next day.
View at shop: HydraPakPrices checked 8 Nov 2026 on each shop's own page; shops can change them. We earn no commission on these links; shops are listed by price. More
Our ratings (out of 10)
1 to 10, compared with the whole market. Each says what it's based on. How we score
Weight for its size
From maker's figures 7/10How much it adds to your pack for the water it holds. 7: Better than most.
HydraPak UK lists 59.8 g for 0.35 L, which includes the hand strap. We round it to 60 g (59.8 g gives 171 g per litre too): 171 g per litre, near the top of the 100–179 g/L band, because the strap adds weight to a small flask.
Packed size (empty)
Estimate from maker's specs: soft bottle: rolls up when empty 8/10How much room it takes up when it is empty, for the water it holds. 8: Clearly better than most.
Estimate from maker's specs
In short
Good for
- Running or fast walking with a bottle in the hand rather than in a pocket
- Short days where 350 mL is enough, with a refill from a stream or tap
- Clean-water bottle for a 42 mm filter cap (HydraPak lists it as compatible)
Strengths
- 60 g with its strap for 350 mL
- Thumb loop and adjustable hand strap, so you hold it without gripping; it fits either hand
- SpeedFill flip-top cap for one-hand refills; 42 mm opening for ice and drink mix
- Strap comes off for washing, and the flask and cap are dishwasher safe (HydraPak)
- Shrinks as you drink and packs away when empty
Weaknesses
- Only 350 mL: about a third of a 1 L bottle
- Built to be carried in the hand, so it does not suit side pockets or storing water in camp
- No independent test of the current version found, so ease of use and durability are estimates, not reviewed scores
- HydraPak gives no rolled-up size, so we cannot score packed size
Sources
We haven't tested this ourselves. Every score comes from these specs, tests and reviews.