Review on TRIWONDER Collapsible TPU Soft Flasks For Hydration Pack - Ideal For Running, Hiking, Cycling, And Climbing Sports Water Bottles by Anthony Savage

The mouthpiece is simply TOO HARD TO DRINK FROM for running purposes. I’ll continue to use the bottles which are not the same quality as my hydrapak ones, but are completely sufficient. I will note the 500ml flasks hold 450m - not a huge deal. But the difficult draw sucks… or doesn’t suck… I separately purchased two 42mm hydrapak mouthpieces (for $18!) to make them usable in my Solomon running vest. Frankly, over time I would simply rather have more drinkable flasks while running than the extra cash in my pocket. If the hydrapak was a little cheaper I would have just bought them instead but you know… save a few bucks… partially regret the decision afterwards…. Oh well. Customer service did respond to my inquiry about the mouthpieces, and it is just a different design. The short nipple and straw versions have the same design, so draw the same. I think they would be fine for hiking or other activities… but not for me while running.