Ultraspirex UltraFlask 550 Hybrid Running Water Bottle - Ultra Squeezable, Soft and Comfortable, BPA and PVC Free, Made in The USA

Perfect fit

I ordered 2 of these to use in a Momentum 2 running vest. One was fine but the other leaked badly at the cap when held up to drink or when putting back in the vest. I made sure they were tight and swapped the caps between bottles to make sure it wasn't a bottle problem. It turns out it was the silicone gasket inside the cap. One of the gaskets is fine but the other was cut/formed poorly and has about a 1/4" area that is paper thin. I reached out to UltrAspire to see if they would just send me a replacement gasket, but haven't received a response. I ended up returning and the replacement didn't leakI'm not a big fan of the valve. It's rough and blasts out too much water too quickly for me. I prefer a soft bite-style valve personally. Also, the cap will snag your shirt if used in a running vest. I kept wondering why my shirts were getting ruined, initially thinking it was the vest until I realized it was the raised lettering on the cap. Shaving the letters down with a utility knife solved the problem before I damaged any more shirts.

I bought an extra to go with the vest. Unfortunately both the bottle the vest came with and the extra started to leak on the first use. Doesn’t seem very sturdy.

I use 2 of these in my Zygos vest (awesome) for trail running. These are top notch. Very comfortable shape with great squeezability. Very positive closure on mouth pieces that are just the right hardness of rubber. I like the clear ones so I can see exactly what’s in there (and what’s going on in there). I use one for extra water and one for sports drink. Highly recommend!

I have dry mouth and need to have water with me at all times. I find this bottle to be easy to carry and does not drip. I like it so much I now own two bottles

Originally purchased on the off-chance that the bottle fit the Befree filter - it does not. We still use the bottle in our day hike fanny pack, but this darned thing leaks something awful. The pliable plastic that makes these bottles so nice also allows them to deform around the cap, leaking water. It also takes very little pressure for the plug to pop up and gush water. Won't purchase again.

Very comfortable against chest !! High flow rate. No leaks. Company should consider a wider opening for easy ice in. Will order another.

This bottle holds the perfect amount of water for exercise, and the contour makes it very comfortable to carry in my walking vest. Love that it’s dishwasher safe.