We asked a professional guide about his favorite water bottles to take with him into the backcountry

A water bottle is an essential piece of equipment when heading out into the backcountry (BC). At BCs, where hiking and skiing are repeated and the activity level is high, water is essential. It's also a great way to replenish energy with sugar, or enjoy delicious soup or coffee during rest periods. So the question becomes, "What kind of water bottle is best?" There are several things to consider when choosing a water bottle, including not only heat and cold insulation, but also durability in cold weather, ease of use, lightness, and capacity. We asked some experienced professional BC guides what kind of water bottles they usually use and why

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Choices that suit your time and purpose

The type of water bottles you should bring and how many you should bring with you into the backcountry will depend on factors such as the time of year you'll be in the mountains, the length of the tour, and the purpose of the tour. For example, if you're in the middle of winter, you'll want a hot drink to keep you warm on the snowy mountain. However, if it's a sunny, warm spring day, you'll sweat while hiking and get thirsty, and want a cold drink. Professional guides plan their tour itineraries in detail, knowing how much activity there will be that day, including climbing and skiing, and they adjust the drinks they bring to the mountains based on the time of year and weather conditions at the time of the tour

Commonly used for hydration only:

PLATYPUS | Platy 2L Bottle

What our favorite BC guides say

The water bottle is a Platypus 2L. It gets smaller as you use up the contents. It can also be used as a hot water bottle in an emergency. ( Telemark School & Ski Guide Izumiya AK.T | Kenji Akutsu)

On hot days, I use a PLATYPUS hydration system. ( RIKI JAPOW GUIDE | Riki Nakajima)

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It is chosen for its light weight

nalgene | Wide-mouth Tritan 1.0L/0.5L

Nalgene is a favorite among outdoor enthusiasts worldwide thanks to its high-purity plastic and airtight seal. Made in the USA with environmentally friendly saturated polyester resin, it prevents plastic odors from transferring to your drink. The bottle body is resistant to temperatures from 100°C to -20°C, making it lightweight and durable

The unique cap system completely seals the bottle without using any gaskets, making it easy to clean and hygienic

The 1.0L is Nalgene's most popular bottle. It's available in both wide-mouth and narrow-mouth varieties. It's widely used in a variety of situations, from outdoor activities to everyday use. Even the same wide-mouth Tritan 1.0L bottle comes in a variety of colors and graphics, making it fun to choose

◆Official website is here

What our favorite BC guides say

Put a 500ml Nalgene in a thermal case and fill it with boiling sports drink.
Then, put in a 500-1000ml Thermos. A thermos with a large cup that a child would carry is convenient. I think it retains heat just as well, and it's cheap. ( Kuroda Mountain Guide Office | Kuroda Makoto)

I don't know the model of the Tiger Thermos, but I've been using the 0.5L size for over 15 years and it hasn't lost its heat retention.
And the Nalgene 1L. It doesn't break! ( LOCUS GUIDE SERVICE | Furuse Kazuya)

I love
Nalgene I use Nalgene bottles to store things like oral rehydration solution. The wide-mouth 0.5L size is convenient. I use
Thermos for hot water. In winter, I use the 0.75L Thermos. In spring, I use the 0.5L. ( Rhythm Works | Asahi Ryuta)

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It is chosen for its warmth and ease of use

THERMOS | Mountain bottle

This "mountain bottle" is designed for the harsh conditions of the mountains. Nicknamed "Yamasen," it has garnered overwhelming support from climbers and mountain guides. Its secure silicone body ring, shock-resistant bottom cover, and simple screw that's easy to use even with gloves on make it the ultimate in ease of use on snowy mountains

	FFX-901	FFX-751	FFX-501
capacity	900㎖	750㎖	500㎖
Heat retention effect * (6 hours)	Over 80°C	Over 78°C	Over 77°C
Cooling effect * (6 hours)	Below 9°C	Below 10°C	Below 10°C
weight	380g	360g	280g
price	￥7,150	￥6,600	￥6,050
Color	Available in three colors: Matte Red, Matte Black, and Matte Stainless Steel	Available in three colors: clear stainless steel, matte black, and sand beige	Available in three colors: sand beige, matte black, and clear stainless steel
Dedicated pouch	￥2,640	￥2,420	￥1,980

*The heat retention effect is the temperature of hot water when the product is filled with hot water up to the bottom of the middle cap at room temperature of 20°C ± 2°C, and when the water temperature is 95°C ± 1°C, the middle cap and cup are attached and the product is left standing upright for 6 hours. The cold retention effect is the temperature of water when the product is filled with water below 4°C up to the bottom of the middle cap at room temperature of 20°C ± 2°C, and when the water temperature is 4°C ± 1°C, the middle cap and cup are attached and the product is left standing upright for 6 hours

◆Official website is here

What our favorite BC guides say

Bottle: 900ml Mountain Special Bottle. Its heat retention is unparalleled. I fill it with piping hot water. ( Telemark School & Ski Guide Izumiya AK.T | Kenji Akutsu)

I love the Thermos Mountain Bottle 900mL or 500mL. It's incredibly easy to use! ( Vertical Land | Hiroki Ito)

Mountain-specific bottle, 750ml. It won't get in the way even if you put it sideways in your backpack. ( Tyrol | Iwao Saeki)

THERMOS 500ml. I love it for its light weight, slim silhouette, and moderate heat retention. ( COLOR SPORT CLUB | Tomohiro Shagawa)

The THERMOS 350ml is for tea, coffee, etc.
The Mizu 500ml or Yamasen 500ml are for hot water only. ( RIKI JAPOW GUIDE | Riki Nakajima)

THERMOS Mountain Bottle 0.5L. The most reliable bottle for heat retention. ( Infield | Toyokazu Nakano)

THERMOS Mountain Bottle: Lightweight and easy to handle even with gloves on.
Reliable and with impressive heat retention. ( Bantei ~bamboo tail~ | Yuu Takeo)

THERMOS! Excellent heat retention. ( Kazuya Igarashi, Kagura Powder Station

I carry a THERMOS mountain bottle. I rarely drink anything on a one-day tour, so I carry it with me just in case. ( Epic Japan | Akiko Nakae)

THERMOS! Trust and proven track record ( Daichi Terui )

A rival to "Yamasen" and also highly trusted for its heat retention

mont-bell｜ALPINE THERMO BOTTLE

This lightweight, compact thermos bottle, designed for mountain climbing, offers exceptional heat retention even in extremely cold environments. The exterior is made of durable SUS304 stainless steel, while the interior is made of exceptionally corrosion-resistant SUS316 stainless steel. Its silicone rubber non-slip grip and inner cap that opens and closes with a half-turn make it easy to use even when wearing gloves. You can choose between a direct-drinking version for quick hydration or an inner cap/cup version with enhanced heat and cold retention, depending on your needs

The 0.5L model was also awarded the OutDoor INDUSTRY AWARD 2016 WINNER at the OutDoor Show 2016, Europe's largest international outdoor trade fair

	BOTTLE 0.9L	0.75L BOTTLE	0.5L BOTTLE	BOTTLE 0.35L
capacity	900㎖	750㎖	500㎖	350㎖
Heat retention effect * (94°C at start → 6 hours later)	Over 81°C	Over 80°C	Over 78°C	Over 74°C
Cooling effect * (starting at 4°C → 6 hours later)	Below 70°C	Below 80°C	Below 8°C	Below 10°C
weight	380g	360g	265g	240g
price	￥4,950	￥4,400	￥3,850	￥3,300
Color	Available in two colors: stainless steel and red	Available in three colors: dark gray, red, and stainless steel	Available in four colors: dark gray, red, stainless steel, and green	Available in four colors: green, dark gray, red, and stainless steel

*The effectiveness of heat retention and cold retention is measured when the product is filled with the specified amount of 95°C hot water (4°C cold water) and left for a specified period of time (6 hours) at room temperature of 20°C (±2°C)

What our favorite BC guides say

I don't have any particular preferences, but I use the Mont-Bell Alpine Thermo Bottle 0.9L.
Whether it's Mont-Bell or a THERMOS mountain bottle, I recommend something with good heat retention in winter. ( Circle Game Guide Service | Shohei Sasaki)

Mont-Bell's Alpine Thermo Bottle 0.5L! Excellent heat retention. ( Mountain Guide Coyote | Ryuta Furuichi)

I carry a Mont-Bell 0.35 and two Thermos 0.15 or 0.18 bottles. The larger one is for emergencies (if you drink it, it will constantly spread and cool down while you're out), and I never use it all up. I only drink small bottles and chilled 500ml PET bottles. ( Hokkaido Backcountry Guides | Tsukahara Satoshi)

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