BRAIN SLEEP PILLOW

It's made in Japan, manufactured in Kusu Town, Oita Prefecture. The material is 100% polyethylene fiber, a recyclable, sustainable material.

The 100% polyethylene fiber material is a high-resilience material in which countless fibers act like tiny springs. Unlike cotton or polyurethane, which sink softly under weight, it's characterized by firm, springy support for your head.

That said, the Brain Sleep Pillow is different from a typical polyethylene pillow. Its unique 3-layer, 9-gradation structure is soft in the center and gradually firmer toward the edges, creating a natural fit that doesn't feel like the material's inherent firmness. Because it conforms to your head whether you sleep on your back or your side, users often describe it as offering "a new kind of feeling — springy resilience combined with a soft, enveloping fit."

It also gradually molds to your own head shape and sleeping posture the more you use it, so even if it feels firm at first, it becomes more and more comfortable and personalized to you with continued use.

In general, we recommend STANDARD. If you prefer something taller, choose HIGH; if you prefer something lower, choose LOW.

See how to choose the pillow that's right for you Please try it for at least a week first. If the height still isn't right, a one-time size exchange is available within 30 days of arrival (limited to the Brain Sleep Pillow LOW, STANDARD, and HIGH models). Please note that a second exchange or return after the first exchange is not possible.

If you'd like to exchange your pillow, please send the following information through the Contact Form. *The exchange service is only available for purchases made through the BRAIN SLEEP OFFICIAL SITE or official BRAIN SLEEP online shops (Rakuten Ichiba, Yahoo! Shopping, Amazon). *To confirm your purchase history, we will ask for your order number when you request an exchange.
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【Order number】
【Purchased size】
【Desired exchange size】
【Duration of use (*Please try it for at least a week first)】
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For Brain Sleep Pillow size exchanges, the process is handled via simultaneous pickup: when your replacement pillow is delivered, you hand your current pillow to the delivery driver at that time.
*We cover the shipping cost for this simultaneous pickup.
*Please note that we cannot accommodate exchange requests outside of this simultaneous pickup method, such as if the product is not on hand at the time of delivery.
*Please keep your pillow cover — if you send it along with the item for exchange, we will not be able to return it to you.
*If you purchased through Amazon, Rakuten, or Yahoo! Shopping Mall, you will need to register as a member on the BRAIN SLEEP OFFICIAL SITE in order to process a size exchange.

The warranty period is one year. If there is a quality issue with the product, we will address it within the warranty period.

It's a new kind of purchasing experience — try it first, and continue only if you're satisfied. You can try it thoroughly at home for 30 days.

Try it at home 30-day trial service ›

It has demonstrated high durability in tests simulating roughly six years of use (43,200 compression cycles). You can also take advantage of our Eco Cycle Program, which lets you exchange your pillow for a new one at ¥10,000 off your next purchase (see Eco Cycle Program details / requires online purchase and member registration).

It's also available at authorized retail stores. Product lineups vary by store, so please check here for details.

When you're concerned about dirt or odor
Rinse the entire pillow with shower water. If dirt or odor is a particular concern, use a diluted neutral detergent. After washing, dry it flat in a well-ventilated, shaded area. If you want it to dry faster, wrap the pillow in a bath towel and gently shake it up and down to remove excess water before drying.

When the height starts to feel off (once every 1–2 months)
STEP 1: Pour 45–50°C hot water over it for about 60 seconds
Place the pillow flat and pour hot water over the areas of concern. Avoid pouring water while the pillow is propped up or under weight, as this may cause it to deform.K

STEP 2: Pour water over it for about 15 seconds to set the fluffiness
Regular tap water temperature is fine. *On extremely hot summer days, tap water temperature may rise, reducing the effect.

STEP 3: Dry it in a shaded, well-ventilated place
Lay the pillow flat to dry. Avoid direct sunlight or warm-air drying. If you want it to dry faster, wrap the pillow in a bath towel and gently shake it up and down to remove excess water.

We also offer the "Brain Sleep Pillow Adjust Sheet," which lets you fine-tune the height of your Brain Sleep Pillow so it can always provide the best fit, no matter how you're feeling that day.

[Common precautions for care and maintenance]
Avoid caring for the pillow while it's propped up, folded, has something placed on top of it, or is under weight, as this can cause wrinkle-like lines or dents.
Do not pour water hotter than 51°C onto the pillow.
Avoid drying it in direct sunlight or with warm air.
Hair products or cosmetics may cause discoloration. Please note that once the material itself has discolored, care and cleaning cannot restore its original color.

The pillow cannot be washed in a washing machine or dryer, or ironed. Doing so may damage the material and impair its performance. Please clean it by rinsing with shower water instead.

The pillow has a marker to indicate its front and back. Please use it with the marked side facing down, and don't remove the marker. If you can no longer tell which side is which, check by touch: the side with finer, softer fibers is the front, and the side with thicker, firmer-feeling fibers is the back.

You can choose based on the sleeping feel you're looking for.

• Active Air: Prioritizes breathability. Recommended for those concerned about heat or night sweats. *Because of its mesh structure, it may leave marks on your cheek when sleeping on your side.
• Organic Sleep: A gentle touch derived from organic cotton. For those who prioritize the feel of natural materials.
• Perfect Cool EX: A cool-to-the-touch type. Recommended for summer or for those who tend to feel hot.

Place the pillow with the mesh side of the cover facing down and the firmer side of the pillow facing up. After tucking in the cover's flap to adjust it, flip the pillow over before use. *Please use the pillow so that your head rests on the side with the mesh.

Even during the day when you're not using the pillow, store it somewhere that avoids high heat and humidity, and don't place any weight on top of it. Avoid storing it in direct sunlight or in places that get hot.