Our largest backpack, ONE.

The ONE will always offer you comfortable hiking in the rocky sections, ridges with chains, or steep uphills in the Japanese hiking trails. We offer five sizes of torso lengths and four sizes of hip belts for each hiker, and a uniquely designed X-shaped carbon frame fits your torso comfortably and lets you move with ease.

The ONE uses a proprietary 200 denier high-density nylon with extremely tough ultra-high-molecular-weight polyethylene 100% Technoforce® Steel (used only for the front and side pockets).
※Technoforce® Steel (TS White) uses a different material, increasing the price at ¥54,000 Tax included.

– The X-frame’s carbon pole diameter has been increased from 3 mm to 3.5 mm, improving rigidity and making it easier to carry heavy loads.
– The bottom attachment loop has been standardized across the MINI, MINI2, and THREE models.
– The position of the brand name has been centered.

– Compression cord buckles and guyline components have been reduced in size.
– Compression cord thickness adjusted to 2 mm and gear loop to 2.5 mm.
– The side pocket pattern has been revised for easier bottle insertion.
– The hydration hose port has been removed.

– The sewing method of the shoulder strap adjustment tape has been revised to enhance durability, and the slack has been increased from level one to level two, making it compatible with various shoulder strap options from different manufacturers.
– The hip belt has been reinforced with a core and piping around the edges, improving durability and rigidity for easier carrying.
– The emergency whistle color has been changed to black.
– The material for the shoulder straps and back has been upgraded from 200D Oxford to 200D HT PC coated ripstop nylon.

– Adjustments have been made to the parts and patterns of the side pockets for easier access and operation while in motion, with slight relocation of the opening to the front to make it easier to reach.

– The interior fabric for the front pocket and the main body is nowlight gray instead of white.

The following products are images of the 2023 model, so some details may differ.

Located in the back of the pack is a uniquely designed X-shaped carbon frame that fits your torso comfortably and lets you move with ease.

Conventional large-volume backpacks are designed to distribute the load around your waist. However, ONE’s X-shaped carbon frame, waist stabilizers, and shoulder lifters allow full control of the load distribution to fit your needs to direct the load to your waist or upper body, achieving the best load balance for each of you.

*The above function is enabled by the highly flexible carbon frame. But please note that the carbon frame itself is not so strong, so our recommended comfortable maximum load for ONE is 11 kilograms.

When encountering a steep uphill or rocky terrain, free your waist to distribute the load on your upper torso, so that you can walk comfortably using the entire lower part of your body.

1. Loosen the waist stabilizer straps.
2. Tighten the shoulder straps to keep the backpack closer.
3. Tighten the shoulder load lifters.

When getting tired, distribute the load on your waist to alleviate the upper torso fatigue, allowing you to go on walking further. We also recommend the load to be distributed on your waist on flat terrain.

1. Slightly loosen the shoulder straps.
2. Tighten the waist stabilizer straps to keep the carbon frame close to your waist.
3. Tighten the shoulder load lifters to keep the pack closer to your back. (Do not pull too tight.)

Our ONE is perfect for long hikes for many days. You can be creative and use the top strap, bungee cords and bottom attachment loops to carry even more.

1. Please make sure the hip belt is correctly positioned.
2. Insert the hip belt through the attachment area.
3. Attach the center Velcro of the hip belt to the body, which also has the Velcro side.
4. Pass the hip stabilizer straps through the plastic parts of the body.

In the below section, we will show you a packing example in the no-snow season from one of our good friends.

The best way to pack the ONE depends on each hiker. It depends on when, where, why, and how long you hike. Below is just one example of how you could pack the ONE.

*For the reasons below, it is recommended to pack a sleeping bag directly, without its stuff sack:

• By packing without the stuff sack, the fill power of the sleeping bag stays fresh.
• The softness of the sleeping bag enhances the comfort around the hip.
• The bottom part becomes softer and makes it easier to access the water bottle in the side pockets.
• The sleeping bag swells and fills the gap inside the pack, thus improving the stability.
• The light sleeping bag is allocated at the lower part, while the heavy items are at the upper part, providing a good load balance and comfort.

This 200 denier high-tenacity (HT) nylon, interwoven with ripstop threads, boasts excellent tear resistance for its weight. The fabric has a water-repellent coating on the surface and a polycarbonate (PC) coating on the back which is significantly resistant to hydrolysis, ensuring minimal degradation even after 10 years in “jungle tests.”

200D HT PC Coated Ripstop Nylon 139g/m²

The fabric made from 100% ultra-high molecular weight polyethylene (UHPE) is exceptionally lightweight yet strong; light enough to float on water yet theoretically capable of supporting around 20 tons with just a 10 mm diameter. This high-density woven fabric offers world-class tear resistance, tensile strength, and abrasion resistance. Its hydrolysis-resistant PC coating on the back further enhances long-term durability, with “jungle tests” showing no significant changes after 10 years. UHPE does not retain water, preventing the fabric from becoming heavier when wet.

The fabric will become more soft and wrinkles will decrease with use.

Technoforce® Steel 98g/m²

*All test data are in-house measurements.

In the diagram below, the higher the blue value, the heavier the fabric, while higher black values indicate greater strength.

This 70 denier HT (high-tenacity) ripstop nylon fabric is our proprietary material with enhanced strength and durability compared with conventional nylon. The surface is DWR (durable water repellent) finished, and the backside is polycarbonate coated, achieving a much better anti-hydrolyzation performance than regular polyurethane-based fabrics.

70D HT PC Coated Ripstop Nylon 106g/m²

We offer five sizes of torso lengths and four sizes of hip belts. To define the size correctly, we recommend that you try on the product before purchase.

*The torso length refers to the length of the back bone, which we define as the length measured from the C7 vertebra to the hipbone.

*The hip belt size is not your waist size. To define the hip belt size correctly, make sure you wrap your tape measure around your hipbone.
If you can’t decide between two sizes of the hip belt, we usually recommend the smaller size so that you can tighten it firmly.

Decide your torso length based on the jutting, upper edge of the pelvic bone at each side of your hipbone.

1. Find the jutting of each side of your hipbone, and align your pants’ waistband on the juttings. The level of the waistband is where the hipbone should be.
2. Find the backbone and extend the tape measure from the waistband to the back of your neck.
3. Slightly tilt your head forward to find the bump of your back neck (7th cervical vertebra, or 7C vertebra) and measure the distance from the waistband to the 7C vertebra.

*The length from the edge of the waistband to the 7C vertebra is defined as the torso length. To define the hip belt size correctly, make sure you wrap your tape measure around your hipbone.

*The above should only be used as a rough guide. Please note that torso length may vary depending on your body shape. Wrap your tape measure around your hipbone. Your hip belt size cannot be determined by your weight and height.

In the event that the carbon rod attached to the back of the main body gets damaged, we offer a free replacement within one year of purchase.

If damage occurs, please contact Yamato Michi Customer Support through the Contact Us page, including your order number. We will provide guidance on the procedure and arrange for the product replacement.

– The ONE is water repellent finished, but not water-resistant. The pack cover is useful but does not make your backpack waterproof. Use a pack liner or Ziploc bags to keep your items inside dry.
– Bug Spray with DEET can melt the fabric used for the ONE. Avoid getting DEET on the backpack.

• Hand-wash only. Do not machine wash.
• Submerge the product in lukewarm water with a correct amount of neutral detergent, and hand-wash it.
• Do not bleach. Do not use fabric softener.
• Remove any optional parts such as pads and carbon rods before washing.
• Wash off any noticeable stains or smudges with a washing brush or soft sponge.
• Rinse well so that no detergent remains.
• Drain the backpack with the mouth down. Keep dry in a shade.
• Store in a dark, well-ventilated place.
• Do not iron.

Technoforce® Steel with hydrophobic properties is naturally a stain-resistant fabric, but due to its white color, dirt becomes noticeable. Here are care methods for three common types of stains.

The longer a stain remains, the harder it is to remove. Clean as soon as possible to keep clean.