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Aisle

BOOST Bikini (4X-5X)

BOOST Bikini (4X-5X)

Clearance - Final Sale
Size
Color:
Our lowest rise style with bold statement waistband. Wear to replace or back up single-use period products.

Details

Includes a bonus absorbency booster for heavy days. Tuck ends into pockets & bleed on.

Absorbency

Holds 8+ tampons worth with our booster. Let the crimson wave flow.

Materials

Body: 48% TENCEL™ lyocell, 48% organic cotton, 4% spandex
Gusset: 90% Truetex™ (88% recycled polyester, 12% organic cotton), 10% TPU
Lining: 86% recycled polyester, 14% organic cotton
Booster: ​65% recycled polyester, 24% polyester, 11% hemp
All materials are OEKTO-TEX certified and lab tested for PFAS. No detectable levels of PFAS to 1 part per million.

  • Made with TENCEL & organic cotton
  • Machine wash & dry safe
  • Replaces 100+ disposable products
View full details

Boost the Absorbency

Each pair of Aisle Boost underwear comes with a removable absorbency booster that adds an extra 4 tampons of absorbency. It's an innovation that sets these period underwear apart from the rest.

For heavy flow-ers there's no need to change your undies part way through the day, just tuck a Booster in and swap it out as needed.

Made with TENCEL™

The fiber that powers our period underwear. One of the most sustainable materials in the world - TENCEL™ Lyocell - is biodegradeable, highly breathable, less susceptible to odour-causing bacterial growth, and absorbs 50% more than cotton.

Our Tech

Featuring Truetex™ Fabric Technology

We developed our own custom blend of materials to create a gusset that's moisture wicking, super absorbent & leakproof without the use of harmful chemical finishes. Our undies keep absorbing, wash after wash after wash.

Learn More

FAQ

How do your period undies work?

Our specially engineered lining combines super-absorbent Truetex™ technology with a leak-proof lining that absorb 4 tampons worth of fluid. Use the removable booster for an additional 4 tampons of absorbency.

Do Aisle undies contain PFAS?

<b>No detectable levels of PFAS</b> have been found in our underwear, based on a detectable limit of one part per million.

Do I need to wear a pad or tampon with them?

Nope! Our undies were built to completely replace pads and tampons. They make great backup protection with tampons or menstrual cups, too.

What does the booster do?

Our undies absorb 4 tampons worth of fluid on their own, but if you need a little extra you can add the optional booster for an extra 4 tampons worth. Just tuck the ends into the slits at either end of the gusset.

How do I wash my Aisle undies?

Our undies were made to fit into your regular laundry routine. Just rinse the gusset in cool water before washing in the machine with your regular laundry. Hang to dry where possible - it saves energy and prolongs the life of your undies!

Real reviews from real people

Write a Review
average rating 4.5 out of 5
Based on 284 reviews
  • 5 Stars
    199 Reviews
  • 4 Stars
    57 Reviews
  • 3 Stars
    15 Reviews
  • 2 Stars
    7 Reviews
  • 1 Star
    6 Reviews
93% of reviewers would recommend this product to a friend
Absorbency
Rated 4 out of 5
Comfort
Rated 4 out of 5
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Customer photos and videos
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284 Reviews
Reviewed by Erin K.
Verified Buyer
BOOST Bikini (4X-5X)
Reviewing
BOOST Bikini (4X-5X)
I recommend this product
Flow
Moderate
Height
5'2
Hip
37" - 38"
Size
S
Rated 5 out of 5
Review posted

Where would I be without these?!

An essential! Previously a lifelong tampon/cup user, because i don’t like the feel of a pad, these are essentials to me now

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Absorbency
Rated 4 out of 5
Comfort
Rated 5 out of 5
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Was this helpful?
Reviewed by Olivea D.
Verified Buyer
BOOST Bikini (4X-5X)
Reviewing
BOOST Bikini (4X-5X)
I recommend this product
Flow
Very Heavy
Height
5'4
Hip
45" - 46"
Size
1X
Rated 5 out of 5
Review posted

Super comfortable!

Nice coverage front and back. I have a pretty heavy flow and it hasn't leaked through the extra cloth pad yet. Very comfortable.

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Absorbency
Rated 5 out of 5
Comfort
Rated 5 out of 5
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Was this helpful?
Reviewed by Karen
BOOST Bikini (4X-5X)
Reviewing
BOOST Bikini (4X-5X)
I recommend this product
Rated 5 out of 5
Review posted

5 Stars

Insanely comfortable and really effective even with high flow. These are a game changer!!

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Reviewed by Jennifer M.
Verified Buyer
BOOST Bikini (4X-5X)
Reviewing
BOOST Bikini (4X-5X)
I recommend this product
Flow
Very Heavy
Height
5'3
Hip
35" - 36"
Size
S
Rated 5 out of 5
Review posted

Great for overnight

Love using these for overnights on heavy days paired with a menstrual cup. I sized up from the suggested size as I don't like too skimpy a fit and I'm always weary of shrinkage in the wash/dry. Happy with my choice.

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Absorbency
Rated 4 out of 5
Comfort
Rated 4 out of 5
Fit
Rated -1 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Was this helpful?
Reviewed by Jenny L.
Verified Buyer
BOOST Bikini (4X-5X)
Reviewing
BOOST Bikini (4X-5X)
I recommend this product
Flow
Very Heavy
Height
5'3
Size
S
Rated 5 out of 5
Review posted

Comfy and I love the boost option and no pfas!

Snug but still comfy. My flow is very heavy for days so having a booster option and it fitting snuggly makes me less worried about leaks. This underwear feels like quality compared to period underwear I bought that is thin. So it will show through in leggings but better that than my period has every time with the thin ones. I'm also relieved it doesn't have pfas.

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Absorbency
Rated 5 out of 5
Comfort
Rated 5 out of 5
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Was this helpful?