The ONE Custom Edition can be custom-ordered according to your preferred fabric and color. The customizable parts are as follows:

• An additional fee applies for some fabric options.
• The back panel fabric cannot be customized.
• Order periods are set irregularly and will close once the maximum number of orders is reached.
• Please note that production starts after we receive your order, so delivery will take some time.

For detailed product information, please refer to the ONE product page.

The examples of custom orders are shown below. Please note that some zippers and fabrics are currently discontinued and unavailable:

• To better conform to the curve of the hips, we added L-shaped stitching to the rigid hip belt, creating a secure, wrap-around fit that supports the entire waist.
• The design has been updated with dual webbing straps—one at the top and one at the bottom—for easier tightening and a more contoured, three-dimensional fit to the body.

With the ONE Custom Edition, you can choose the fabric and color for different areas of the backpack. Fabric options include our proprietary Pertex®︎07RS-PC and Pertex®21RS-PC developed in collaboration with Pertex, the lightweight yet exceptionally strong Technoforce® Steel, X-Pac VX07, and UX10—the lightest X-Pac currently available.

Available for: Roll-top/Body, Front pocket

A proprietary 70-denier fabric, developed in collaboration between Yamatomichi and Pertex. Designed with an optimal weave and a supple structure that disperses impact, this fabric delivers the lightweight performance essential for backpacks while offering strength that surpasses standard nylon. A special polycarbonate coating adds extra durability by resisting moisture-related wear over time.

Available for: Front pocket

A proprietary 210-denier fabric, developed in collaboration between Yamatomichi and Pertex. With an optimal weave and a supple structure that disperses impact, this fabric balances the lightness needed for backpacks with strength that surpasses standard nylon. A special polycarbonate coating adds extra durability by protecting against moisture-related wear over time.

The 2025 Spring/Summer model will be available in the five colors below, with sales starting in June.
Price: ONE (¥52,000) / ONE TS White (¥57,000)

At 85g/㎡, this is the lightest fabric in the X-Pac lineup. It features a multi-layer construction: a 100-denier ultra-high-molecular-weight polyethylene (UHPE) with a cire finish (high-density treatment) for added firmness, reinforced with a aramid cross-ply, and backed with a polyester film. This combination offers exceptional strength and waterproof performance while remaining lightweight.

When new, the fabric feels notably stiff, but with use, it quickly softens into a supple texture while retaining a crisp structure.

Available for: Front pocket

X-Pac VX07 is a multi-layer fabric comprised of 70 denier nylon on the surface, a water-resistant polyester film in the middle, and a 50 denier polyester taffeta and diamond-patterned black polyester X-Ply material at the back. It is highly durable and water-resistant with hydrostatic water-resistant structural technology.

Available for: Bottom

X-Pac VX21 is adopted for the bottom material of our standard backpacks. It is a multi-layer fabric composed of 210 denier nylon on the surface, a water-resistant polyester film in the middle, and a 50 denier polyester taffeta and diamond-patterned black polyester X-Ply material at the back. It is highly durable and water-resistant with hydrostatic water-resistant structural technology.

Available for: Front pocket, Bottom

This fabric is made entirely from ultra-high-molecular-weight polyethylene (UHPE), known for its outstanding strength and incredibly light weight—so light it floats on water. Despite being lightweight, UHPE fibers are exceptionally strong; in theory, a single 10mm strand can hold up to 20 tons. The fabric is densely woven to achieve top-tier tear resistance, tensile strength, and abrasion resistance for its weight. On the back, a durable polycarbonate coating adds long-lasting protection, resisting the kind of breakdown that can happen over time with moisture exposure. In demanding durability tests, including the “jungle test” that simulates harsh environments, the fabric showed virtually no signs of wear even after 10 years. And because UHPE doesn’t absorb water, the fabric stays light and never becomes heavy, even in wet conditions.

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

The ONE Custom Edition is a semi-custom backpack that lets you freely choose the fabric and color for the body/roll-top, front pocket, bottom, and zipper from the options below.

The zipper type is chosen to match the fabric’s characteristics. If you select lower-waterproof fabrics like Technoforce® Steel or Pertex® 21RS-PC / 07RS-PC for the front pocket, a lightweight and durable coil zipper is used. For highly waterproof fabrics like X-Pac, a water-resistant zipper is paired to maintain performance. You can choose from 14 color options for the zipper, whichever type applies.

Coil zipper (YKK #5 Coil Zipper)
Technoforce® Steel
Pertex®︎07RS-PC
Pertex®︎21RS-PC

Water-resistant zipper (YKK #5 Aquaguard®)
X-Pac VX07
X-Pac UX10

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.

Please measure around your hip bones (where the bones protrude), not around your waist at navel height. If you’re between hip belt sizes, we recommend choosing the smaller size. A larger size may offer more stability around the hips but could prevent you from tightening it fully when you want a snug fit.

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

1. Find the point where your hip bones protrude the most and align the top edge of your pants with that spot.
2. Use your hand to locate the bony bump at the base of your neck (the seventh cervical vertebra).
3. With your head tilted slightly forward, measure from that bump at the base of your neck down to the top edge of your pants.
4. The distance from the top edge of your pants to the seventh cervical vertebra is your torso length.

This chart is meant as a general guide. Even if your height falls outside the listed range, the torso length might still be the right fit for you. For the hip belt, be sure to measure around your hip bones—size cannot be determined by your weight or height.

• As this is a custom-made product produced upon order, we cannot accept cancellations or changes to your order after the order period ends.
• Cancellations and changes to your order are possible during the order period.
• Delivery may be delayed due to production issues or other unforeseen circumstances.
• Fabric colors may vary slightly depending on availability and production timing.
• Limited to one item per customer.
• We do not accept returns or exchanges due to customer preferences.

For any questions, please feel free to contact us here.

• 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 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.

We will ship by DHL for overseas customers (excluding China, Hong Kong, Taiwan, Korea and Russia). For customers in China, Hong Kong, Taiwan, Korea and Russia, we will ship by EMS. Shipping costs vary depending on your country and region.