Klean Kanteen 40 oz. Wide Mouth Stainless Steel Water Bottle Review

I've had my Klean Kanteen 40 oz. wide mouth stainless steel water bottle since 2008. It's not sexy, it's not expensive, and it's not the item that most gear heads would ever brag about. But it is reliable, durable, and trustworthy. Exactly what you want in a backpacking partner.

Klean Kanteen makes a variety of stainless steel reusable water bottles. This review is specific to the 40 oz. wide mouth model.

Klean Kanteen 40 oz. Wide Mouth Features

• Made from 18/8 Stainless Steel.
• Single wall, non-insulated.
• It has an electropolished interior, which makes cleaning easier than most others. And because it’s made from stainless steel, it’s non-toxic.
• It includes the leakproof wide loop cap with stainless steel bottom to ensure an all stainless inside.
• Compatible with all of Klean Kanteens Wide Caps, including the Café Cap 2.0.
• Dishwasher safe.
• Lifetime guarantee.
• Dimensions: 3.5” x 9”
• Weight: 9 oz

The wide mouth screw cap has a loop for easy carrying. It can be secured to your pack with a carabiner. The threading also fits most backcountry water filters or purifiers.

The cap has a silicone seal that has held up perfectly for the last twelve years of nearly daily use. The only leaks that I've experienced have all been to user error. The cap doesn't require brute force to seal either. Just a snug twist should do.

A nice benefit of stainless steel is that it doesn't impart any flavor. No plastic aftertaste, just water or whatever drink you happen to store in it. This also means that you could use it for wine or beer. A 64 oz. growler size is also available. Other beverages should be fine too!

Compared to a standard wide mouth Nalgene bottle, it is slightly heavier, but it also has an eight-ounce larger capacity. It can also boil water and even pound tent stakes in a pinch. Don't try that with a plastic bottle. When I'm looking to save grams when backpacking, I'll use my Platypus water bladders and used Smartwater bottles.

Besides this 40-ounce size, it is also available in 27 oz., and 64 oz bottle sizes.

Long Term Impressions

Daily Use

Since buying the Klean Kanteen, I've used it most every day. It replaced the Nalgene bottle that I used to carry to work. As a reusable water bottle, it’s also virtually eliminated buying bottled water which means I've probably saved nearly 10,000 plastic water bottles from the landfill.

It has held up to twelve years of nearly daily use despite occasional neglect or abuse. I have dropped it a few times, and it has a couple small dents in the bottom and a number of minor scratches. It's brushed stainless still finish hides these minor scars. I've left it in my car on 100-degree days and the plastic cap and silicone seal works like new.

You can fill it with hot beverages but since this is a single wall bottle, it lacks insulation, and you might want an insulated bottle instead. One advantage for cold beverages is however that it chills down in no time at all.

It's easy to clean and is dishwasher safe. Occasionally I'll give it a thorough cleaning using Bottle Bright cleaning tablets. The wide mouth makes it extra easy to fit a bottle brush in case you need a little extra.

Great for Winter Camping

When I first purchased it, I was looking for a water bottle for winter camping. I wanted a bottle that I could melt snow in as well as to store water. Most people will melt snow in one of their cooking pots. This is fine but why not use another vessel separate from the cooking gear? It seemed like a simpler solution with less chance of spilling water and wasting fuel.

It would also serve the same purpose of plastic water bottles like the several Nalgene bottles that had recently (2008) been recalled due to BPA contamination. Among winter campers, it’s also a common practice to place a hot water bottle inside your sleeping bag to help keep you warm as metal bottles transfer heat well. Of course, It's imperative that the bottle must not leak!

It made sense to me to have one container that I could use to melt snow, store water, and also use for a hot water bottle. Better yet, a stainless-steel bottle should be nearly indestructible.

It's important that you do not use any insulated or double wall Klean Kanteen, or any other brand, to heat water in as it could explode or rupture. Only use single wall vessels to heat or boil water!

Our Verdict

Of all of the backpacking and camping gear that I have bought and used over the last thirty years, I can easily say that my Klean Kanteen has been the most used, most reliable, and best value of all. The price is reasonable especially when you consider how durable and long-lasting that it is.

The bottom line is that the Klean Kanteen has served me very well and has become my favorite bottle. I would not hesitate to recommend it.

Where To Buy

I recommend either REI or Amazon. Both stock it in all the current options including Klean Kanteen's insulated water bottles, as well as accessories like the Café' cap and stainless drinking straw.