I love how adjustable this vest is--the straps on the sides and the elastic in the front can all be made significantly bigger, which totally saved me from not being able to fit this vest at all. There was no size chart available so I took a gamble on the L/XL as a women's size 18 and 40D chest. I just fit with everything adjusted to its largest size. Granted, it does look a little goofy on me because the shoulders are too small (unfortunately not adjustable), but functionally it will still work. I probably would recommend the L/XL for a women's 14 at the highest if you want an ideal fit, me as an 18 is reeeeally pushing it.There are 2 14oz soft flasks for the front and a massive pocket in the back for an additional bladder. There are also extra small pockets on the front for smaller items. I have been bringing my phone (iPhone Pro Max, so it's fairly big), keys, earbuds and a collapsible water dish for my dog and everything fits in the vest fine.My major qualm here is the price point. I know Nathan is regarded as a high-quality brand, but at the end of the day, this is a vest with a couple of soft plastic bottles. I will also note that the lids of the bottles/flasks start clear and they do discolor and yellow over time--doesn't affect their function at all, they just look a little ugly. At $129, I think this is a vest for more experienced (and skinnier) runners, not for beginners like me. And Nathan should definitely add a size chart, especially for women who can have a drastically different fit based on chest size alone.

I am absolutely beyond happy with my purchase of this hydration vest. I know it is a great brand but I have to admit I was worried about fit and comfort. I spent a lot of time reading reviews and looking at options. I am fairly short 5’-5” and I am very “busty”My concern about any hydration pack is that the last thing I need is to carry more weight on my back or my front! Not to mention I have a short waist and I fit but definitely not thin so the last thing I want is something around my waist either. I’ve been carrying water in my hands for years or relying on aid stations because of this dilemma.As soon as I put on the vest I was instantly comfortable. I ordered the XL thinking I could always tighten it up. It fit perfectly like it was made for me. I measured 42 inches around my chest and the fit was on point. I am running a trail ultra in a few weeks and I know this will work great for me. I did 14 miles on Saturday wearing this vest and to my surprise it did not weigh me down. I thought being chesty and having more stuff around my chest would get in my way moving my arms and such but it was perfect! No sloshing no bouncing. It also was light and breathable and did not increase my sweating. I would highly recommend this particular vest for women with a large chest but I’m sure it would be good for any woman as it seems well designed and adjustable no matter your shape. It does allow for a woman’s shape which made me so happy. Also my iPhone Max fit easily into the chest zippered pocket and keys, etc could easily fit too. It was easy to drink out of the soft flask bottles I like this so much better than carrying on my back although that is an option you can add later on. I could see throwing a light weight jacket into the back pocket.Great product!!!!!

The Nathan pinnacle breeze 4 liter hydration vest is now the best running vest I own, and I absolutely love it! I own quite a few running vests, and this vest by far surpasses them all! This vest is in the higher price range of what I own, for reference the ones I owned were in the 50$ -75$ range. In this case there was such a difference in what I got for the price, I can tell an immediate difference in quality with the Nathan hydration vest.First off the fabric is soft and breathable, I love the mesh panels that allows for movement, flexibility, and breathability. The vest itself forms to your body nicely. Next I love the adjustability, you can easily adjust the front to fit your chest perfectly by simply pulling or loosening the cord. I love how easily the cords clasp as well. You can also adjust the sides very easily for the perfect fit.I really love that the sides of the vest actually have mesh panels, my other vests only had a single strap connecting the front and back. The panels make the vest so much more comfortable. Nothing in the vest digs into your skin. The shoulder straps are the same mesh material and they're a nice width, so the vest is supported very nicely.Now for comfort. This is the most comfortable running vest I have worn hands down. It's so breathable, it's very supportive, and the way that it's made the weight is distributed evenly across your body. This vest has so many essential pockets. There's 6 total pockets: 2 to hold your 14 ounce water flasks, 2 in front of the water flask pockets, a zippered pocket for your phone, and a large pocket in the back. The large pocket in the back can be used for an extra 2liter bladder if you have one, plus there's also openings for the bladder hose in the back to go through to the front. If I don't need the extra water, the pocket is great for stuffing it with a windbreaker.The zippered pocket that is also in front is awesome because it actually does hold a phone, even a larger one. I have a decent sized phone and it fit in the pocket great, and I could still stuff something else in there. I love using the extra pockets in the front of the bladder pockets for gels. But i love that you're not lacking any pockets.The Nathan water flasks are top notch, designed perfectly, and right on par with some of the top name brand bladders and water flasks. First off, the pockets themselves fit the water flasks perfectly and there's an elastic band in the pocket to secure them in place. I've had running vests where the water flasks were bouncing up and down as I ran and they were coming out. Also the most genius part, the water flasks have a tall straw that you bite so you can easily get a drink!There is so much attention to detail in this vest, so many little things that are missing in other vest that are little annoyances. But this vest has everything and is so very well thought out. There are also reflective strips in the front for any nighttime running. This vest is aesthetic and was beautifully made. It also looks very chic on. I love the grey color scheme that I got with the light blue accents, which look so pretty together.Also, for the record I got the L-LXL size and it fits great. I'm about a size medium in clothes, and I have an athletic build so my back is a little broader and about a C-D cup size. This vest fits great and I have no issues, I love that it's very adjustable.I can't recommend this Nathan Hydration vest enough. The quality is outstanding and it really is top notch. Yes, it is expensive, but in this case you really do get what you pay for! I highly recommend.

I really love this brand and am once again so impressed with the quality of their products. This product is exceptional quality but also at a premium brand price point. Due this great track record of being impressed, I have already recommended this brand to my athlete friends.For size context, I am Bust 38" Waist 30" Hip 38". I ordered the S-M because there was no sizing chart on the product description. I am larger in the chest (and have larger swimmer shoulders) and can fit. I am going to loosen up the sides for a better fit across the chest area.I am a triathlete who wanted a backpack and hydration option other than a fuel belt while running (road and trails) and carrying water bottles on bike. This hydration backpack is a little more compact and lightweight than my daypack hydration backpack, and i love it!PROs:- Product design/functionality -The number of details are impressive. To list a few: all the zippers, reflective parts, three straps across chest for optimal fit, compartment/pocket dividers- Breathable - close up pictures show mesh-like material that looks durable but breathable- Quality - the fabric is so nice! The buckles and zippers are strong.-Chest Straps - The straps across top are thinner than I am used to but open minded to it since there are three. I like this design as they are easy to adjust around curves in chest and more breathable than larger straps/buckles. I hope they are durable!- Lightweight - With this, it is compact so have realistic expectations on what you want to carry in here (especially if you have added and additional bladder in the back). No issues packing the necessities of ID, phone and fuel.- Functionality - It offers multiple options for different hydration needs. Easy access to fuel, phone, etc.CONs:- It is a bigger brand so more of a premium (and earned) price point.Summary:I have multiple hydration products from this company (fuel belt, handheld and this hydration vest) and I am once again thrilled with their product I will update this review should anything come up with durability! If no update, you can assume that I am still very happy with this product and would definitely recommend if you are looking for a lightweight, compact backpack with hydration option. In fact, I already have recommended this to my athlete friends (trail runners and hikers)!I hope that this review has helped you with your decision. :)

I ordered this for myself for shorter runs where hydration is needed but I don't need to carry a lot of gear. I usually run with an 8 liter hydration vest, and I wanted something a little smaller that I could use on training runs. I ordered this in an XXS-XS size in surf spray. I usually wear a small shirt and an XS in running vests. I found this to be a little loose, even when I tightened all of the available straps (one on each side and the three in the front). Even though I was struggling to get the right fit, the vest is very adjustable and highly customizable in fit.I like all of the front pockets (one on each side plus a zip on the left). The material is soft and breathable, and it washes well. The flasks are 14oz each with long straws. I've never used straws in flasks before, but these worked fine. The flasks were easy to get in and out of the vest even while it was still on. I liked that you can decide where the front bungees attach to the other side of the vest. It was easy to get things in and out of the back of the vest when it was off. I don't think you could get anything in or out while wearing it.There are no extra bungees for attaching shirts, poles, jackets, etc. There is, however, a place to hang a hydration bladder in the back pocket (the back pocket is split into two pockets with a piece of fabric between them). Note that whatever you put in the back pocket closer to your back is going to be touching your back. There is no insulation or padding between the inner back pocket and your back; it’s just a fine mesh. Both pockets go all the way from the top of the vest to the bottom of the vest.I ran a half marathon in this, and I didn't experience any bouncing or chafing.Overall, I highly recommend the Nathan's Women's Pinnacle Breeze 4L Hydration vest for shorter runs (half marathon and under, depending on heat).