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Reviews > Hydration Systems > Bottles > Avex Brazos AUTOSEAL Water Bottle > Test Report by Steven M Kidd

June 10, 2014


NAME: Steven M. Kidd
EMAIL: ftroop94ATgmailDOTcom
AGE: 42
LOCATION: Franklin, Tennessee
HEIGHT: 5' 9" (1.75 m)
WEIGHT: 179 lb (81.20 kg)

Backpacking Background: I've been a backpacker on and off for over 30 years. I backpacked as a Boy Scout, and then again almost every month in my twenties, while packing an average weight of 50+ lbs (23+ kg). In the last several years I have become a hammock camping enthusiast. I generally go on one or two night outings that cover between 5 to 20 mi (8 - 32 km) distances. I try to keep the all-inclusive weight of my pack under 20 lb (9 kg) even in the winter.



AUTOSEAL Insulated Brazos

Manufacturer: Avex
Year of Manufacture: 2014
Manufacturer's Website:
MSRP: US $29.99
Listed Weight: N/A
Measured Weight: Bottle + Lid 13.9 oz (395 g)
Measured Weight: Bottle 11.6 oz (329 g)
Measured Weight: Lid 2.3 oz (66 g)
Listed Height & Width: 11.0 in x 2.75 in (28 cm x 7 cm)
Measured Height: 10.875 in (27.6 cm)
Measured Lid Width: 3 in x 2.625 in (7.6 cm x 6.7 cm)
Measured Base Width: 2.875 in (7.3cm)
Listed Capacity: 24 fl oz (710 ml)
Measured Capacity to Brim: 26 oz (769 ml)

The Brazos AUTOSEAL water bottle is a stainless steel insulated water bottle designed to keep liquids cold for up to 20 hours. It is not designed to keep liquids hot. The bottle uses a lid with a patented AUTOSEAL technology designed to be both spill and leak-proof. The spout is opened for sipping by depressing the AUTOSEAL button and is sealed by releasing it. The body of bottle offers a double walled vacuum seal to create its insulating properties.

It allows for one-handed operation and is BPA free.

The bottle offers a transport clip that allows it to be attached to items like gym bags, backpacks or simply carried with an index finger. The Brazos also offers spout shield that is designed to protect the spout from dirt and germs when not in use or during transport.

The bottle is not intended for use with hot or carbonated beverages. It is not to be microwaved or frozen, and should not be cleaned with cleaners containing bleach, chlorine, abrasives or other harsh chemicals.

The lid is top rack dishwasher safe, however, it also may be cleaned by flushing the spout with warm water or soaked in warm water for at least 10 minutes. The bottle is not to be placed in a dishwasher.


The Avex Brazos appears to be a quality built product in my opinion. Initially when I first picked it up, it felt a very heavy compared to most of my backcountry hydration bladders that weigh in just around an ounce (28 g), but compared to the average sport/recreation bottles I use for exercising it isn't considerably heavier. To clarify, though the Brazos is considerably heavier than my backcountry hydration systems, none of them are insulated to keep liquid cold.

After inspecting the bottle I immediately measured the weight and volume capacity. Both are mentioned in the specifications section, but I'll comment further on the volume capacity. The capacity is listed at 24 oz (710 ml), but I measured it at 26 oz (769 ml) to the brim. However, I quickly learned that one should follow the suggested maximum volume specifications. I state this because the product warnings suggest pressure can build up under the spout seal. I've noticed pressure build up when I've depressed the AUTOSEAL button. When overfilled water/liquid will spit out. This is certainly why I understand both hot and carbonated beverages shouldn't be used in this vessel.
Brazos Spout Closed
Brazos Spout Open/Depressed

I found the one-handed operation fairly simple. I can easily grasp the bottle in my palm and depress the AUTOSEAL with my index finger which opens the spout and allows me to have a sip of the liquid inside. I find this a simple operation with either my left or right hand.

When considering the AUTOSEAL technology I foresee it being a very positive aspect when I'm running on a treadmill. Anytime I've historically used a simply store bought water bottle or any open mouthed bottle I've spilled water on myself when using a treadmill when running at a speedy pace. The only remedy I've seen to this to date has been a bottle with a sip spout. I look forward to testing the Brazos on a treadmill and giving feedback in the field review.

As a minimalist backpacker I find the spout shield and transport clip a little overkill, but I do see the benefit in keeping the spout free of debris and I've already used the clip in carrying the bottle around in the few days I've been using it for recreational use.

Avex claims the Brazos will keep liquids cold up to 20 hours. I haven't done any technical testing to date, but I can affirm some initial use feedback. I've filled the bottle with ice to just below the brim and then filled it with water on several nights. After 7 - 9 hours of sitting in a ~70 F (21 C) bedroom the bottle still had the majority of the ice remaining. I've also found ice remaining up to 12+ hours in similar conditions.
Spout Shield & Transport Clip

I did leave the bottle filled with roughly half full of ice and water in an open Jeep for 3 1/2 hours in 85 F (29 C) temperatures under the open sun. When I took a sip, I noticed the ice had melted and the water wasn't 'cold' in my opinion, but I would subjectively refer to it as 'cool'. It was much more pleasant sip than leaving a comparable 1/2 liter store purchased bottle of water or even a similar aluminum bottle I've used that would be outright 'warm' or 'hot' to the lips.

I've yet to see the bottle 'sweat' or have any form of external condensation.


My initial impressions with the Brazos AUTOSEAL Stainless Water Bottle are quite positive in general. I can certainly foresee myself using the bottle for both exercise and general recreational use without hesitation.

The bottle is certainly much heavier than the typical hydration vessel I regularly use in the backcountry, but none of these provide insulating properties to keep liquids cold for short, must less extended periods of time. I envision myself carrying the Brazos on an outing filled with only ice to both minimize weight and maximize extended cold liquids while in camp. I look forward to measuring how long it keeps water cold in the coming summer months.

The roses I see in the product are that in using it in initial non-controlled tests are that it has kept water/liquids cool or cold for time periods considerably longer than comparable products I've used in the past. Stated simply, it has kept water 'cold' for 7 - 9 hours in normally regulated interior conditions. In particularly warmer conditions under direct sunlight the Brazos kept water 'cool' with no ice remaining after close to 4 hours.

The only thorn I have at this point is the weight of the bottle when using it in the backcountry. At 13.9 oz (395 g) it's heavier than my entire hydration system to include water filtration combined. However, my current system is not designed to keep water cold so I must keep that in perspective.

Thanks to Avex and to for the opportunity to test the Brazos Stainless Water Bottle.

This report was created with the Report Writer Version 1. Copyright 2014. All rights reserved.

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Reviews > Hydration Systems > Bottles > Avex Brazos AUTOSEAL Water Bottle > Test Report by Steven M Kidd

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