Period Swim Twist High Rise Bikini Bottom

The main character on light days, and reliable backup on heavy days. It’s built with a super-absorbent gusset that absorbs period blood without swelling in the water. How? Oh, just our famous leakproof technology.

Layer 1: A silky-smooth top layer that sits comfortably against the skin.

Layer 2: A highly-absorbent middle layer designed with our leakproof technology to absorb up to 1-3 tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling.

Other Features:

- High rise with twist-front waistband

- Bum coverage: Medium

- Super-discreet liner

- 50+ UPF protection

- Pair with matching Double Scoop Bikini Top

Swim, splash, or sunbathe without ever having to struggle with tampons.
Image of a absorbancy surrounding text
Absorbs up to 1-3 regular tampons worth of period blood.
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Rapidly absorbs moisture to keep you fresh and dry.
Image of a light and comfy surrounding text
Thin, subtle, and designed to feel just like regular swimwear.
Image of a machine washable surrounding text
Simply machine wash on cold and lay flat to dry.

The main character on light days, and reliable backup on heavy days. It’s built with a super-absorbent gusset that absorbs period blood without swelling in the water. How? Oh, just our famous leakproof technology.

Layer 1: A silky-smooth top layer that sits comfortably against the skin.

Layer 2: A highly-absorbent middle layer designed with our leakproof technology to absorb up to 1-3 tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling.

Other Features:

- High rise with twist-front waistband

- Bum coverage: Medium

- Super-discreet liner

- 50+ UPF protection

- Pair with matching Double Scoop Bikini Top

Machine wash cold and lay flat to dry. Do not bleach, iron, or dry clean.


Body: 85% Nylon, 15% Spandex

Lining: 85% Nylon, 15% Spandex

Gusset: Fresh Fix Technology®, Polyurethane Film


Additional Product Ingredient Information

For items with a 20% or more discount, you may exchange for another item or return for store credit. No refunds can be accommodated. 

Items marked as “Flash Sale” or “Clearance” are final sale, meaning no returns, exchanges or refunds can be accommodated. No exceptions. 

Please note: Sale items are not eligible for our First Pair Risk-Free Policy.


We offer free standard shipping on all orders over $70. We ship our items via DHL or Canada Post depending on your location. Please allow 1-2 business days for your items to be processed and shipped. During high volume periods, your order may take up to 7 business days to dispatch from our warehouse location.


US Orders: Please allow 3–10 business days for orders to arrive.

International Orders: Please allow 10–25 business days for orders to arrive.

NOTE: Orders placed on Friday after 1 PM will not be processed until the following Monday.

CANADIAN CUSTOMERS: Shop www.knixteen.ca to order in Canadian currency.

FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
nothing is TMI here—we promise.

Our period swim bottoms contain a triple-layer gusset that absorbs your flow and locks in leaks, whether you're in or out of the water. When they go in the wash with detergent, the blood releases through the top layer—leaving your swimwear fresh and clean for next time. Yes, your other clothes will remain stain-free!

Here's the breakdown of our 3-layer leakproof technology:

Layer 1: A silky-smooth top layer that sits comfortably against the skin.

Layer 2: A highly-absorbent middle layer designed with our leakproof technology to absorb up to 1-3 tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling. 

Not always. When your flow is light, our swimwear can be worn alone without any additional period protection. On super heavy days, we recommend wearing a tampon or menstrual cup with your swimwear. Every period is different though, and we recommend doing whatever makes you feel most confident.

Machine wash cold and lay flat to dry. Do not bleach, iron, or dry clean.

Check out our size chart here

Yes! All of our regular price swim bottoms and one-pieces are eligible for a return or exchange within 30 days of delivery, as long as the original sanitary strip and tags are attached. Our swim tops are eligible for a return or exchange within 30 days of delivery with original tags attached.

Absolutely! The leakproof liner built into all of our period swimwear is undetectable, so they look and feel just like regular swimwear.

Our styles are made to fit teen bodies. For period swimwear in adult sizes, please visit Knix.

COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
Reviews
average rating 4.5 out of 5
Based on 104 reviews
  • 5 Stars
    84 Reviews
  • 4 Stars
    6 Reviews
  • 3 Stars
    6 Reviews
  • 2 Stars
    3 Reviews
  • 1 Star
    5 Reviews
88% of reviewers would recommend this product to a friend
Quality
Rated 4 out of 5
Comfort
Rated 4 out of 5
Effectiveness
Rated 4 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Review posted
Reviewed by Amanda T.
Verified Buyer
I'm a...
Adult
I purchased for...
A Teenager/Tween
Band Size
N/A
Pant Size
Teen 00-2
Size Purchased
S
Usage
  • Pool
Rated 5 out of 5

Swim bottoms

Fantastic product !!

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Effectiveness
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?
Review posted
Reviewed by Monique L.
Verified Buyer
Period Swim Twist High Rise Bikini Bottom
Reviewing
Period Swim Twist High Rise Bikini Bottom
Band Size
N/A
Pant Size
Kids 12-14
Size Purchased
S
Usage
  • Pool
  • Beach
  • Sun Bathing
Rated 5 out of 5

Love!

My daughter loves the high waist fit and the absorbency! Perfect for all the summer fun!

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Effectiveness
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?
Review posted
Reviewed by Katrina P.
Verified Buyer
I'm a...
Parental Figure
I purchased for...
A Teenager/Tween
Band Size
N/A
Pant Size
Teen 12-16
Size Purchased
S
Usage
  • Pool
Rated 5 out of 5

It works great!

The bottoms looks so cute, you can't tell that they're period swim! I was surprised at how effective they are, I wish I knew about them earlier!

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Effectiveness
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?
Review posted
Reviewed by Cyndie R.
Verified Buyer
Rated 5 out of 5

Worked Great

Got these for our tween. She loves to swim and was so happy she didn't have to sit out a week per month this summer.

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Review posted
Reviewed by Jacci D.
Verified Buyer
Band Size
N/A
Pant Size
Teen 12-16
Size Purchased
L
Usage
  • Pool
  • Beach
  • Sun Bathing
Rated 5 out of 5

High waisted bikini bottom

Worked great!

Loading...
I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Effectiveness
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?