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Home / Shop All Teen / Teen Period Swim Square Neck One-Piece
KnixTeen

Teen Period Swim Square Neck One-Piece

$88.00 USD

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Absorbs about 3 regular tampons

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Full coverage style

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Flattering square neckline

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Premium UPF 50+ fabric

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Machine washable

| Black
| Black
| Black
| Black
| Black
| General

Absorbency: Moderate
Drop
Drop
Drop
Drop
Drop

Color: Black

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

Shipping

Shipping
Processing Time

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order.

Delivery Time

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges

Orders over $100* USD = Free standard Shipping (4-8 business days)**
Expedited = $4.99 USD (3-6 business days)**

Orders under $100* USD = $7.99 USD Standard Shipping (4-8 days)**
Expedited = $9.99 USD (3-6 business days)**

*After discounts, before shipping and taxes. Processing times not included in estimates.
**Military Addresses Excluded. Standard Military Address Shipping = $10.00 USD (est. varies per location)
Easy Returns within 30 Days

Returns

Returns

Free Returns

Knix covers the return shipping fees for exchanges and refunds initiated through our Return & Exchange Portal. Exchange orders initiated through our Return & Exchange portal are also eligible for free shipping within the USA and Canada. Please note, the shipping fees on your original order are non-refundable.

Return Policy

Return policy varies by product, please check if your item is refund or exchange eligible by viewing our full policy here.

Sale & Last Call

Items discounted below 30% are eligible for size exchange or store credit. Items discounted 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.
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Swim in Style

A sporty style with a square neckline, built-in shelf bra and removable cups.

Worry-Free Protection

Discreet, built-in protection that absorbs about 3 regular tampons worth.

Stay Sun-Safe

Premium UPF 50+ fabric shields you from UV rays while you relax, swim, and play.

Zoom

| Black
| Black
| Black
| Black
| Black
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Everyday Wear
  • • No leakproof protection
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

Drop
Drop
Drop
Drop
Drop
  • • light period days
  • • sweat
  • • discharge
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

Drop
Drop
Drop
Drop
Drop
  • • moderate period days
  • • light bladder leaks
  • • sweat
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

Drop
Drop
Drop
Drop
Drop
  • • extra heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
LEAKPROOF SWIM WORKS IN LAYERS

Built-in protection that feels like nothing at all.

Looks just like regular swimwear. Non-swelling liner and patented no-show design.

Soft Top Layer

Top Layer

Smooth and comfortable liner in swimsuit fabric.

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4.6
Rated 4.6 out of 5 stars
Based on 38 reviews
Total 5 star reviews: 33 Total 4 star reviews: 1 Total 3 star reviews: 1 Total 2 star reviews: 1 Total 1 star reviews: 2
89%would recommend this product
ComfortRated 4.7 on a scale of 1 to 5
FitRated -0.3 on a scale of minus 2 to 2
EffectivenessRated 4.7 on a scale of 1 to 5
Ease of UseRated 4.0 on a scale of 1 to 5
Write a Review (Opens in a new window)
38 reviews
  • Rated 5 out of 5 stars
    13 hours ago
    Good fit!

    This is a good fit. The cut offers great coverage. Washes well.

    Chir C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Lovely fit and comfortable

    Functions as described and has a flattering and comfortable fit.

    Chanta B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Perfect fit!

    The suit fits true to size and you would never know it is reinforced. It’s quite modest as well. The adjustable straps are a great option.

    Heather G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Period Swim Square Neck One-Piece

    This is great for my 11-year old for swimming!

    Christina P.
    Verified Buyer
    Was this helpful?
  • Rated 1 out of 5 stars
    3 months ago
    TERRIBLE

    PLEASE DONT BUY THIS PERIOD SWIM. IT WILL NOT PROTECT YOUR DAUGHTER FROM A HUGE LEAK. I WISH I NEVER BOUGTH THIS FOR MY DAUTHER.

    Paola R.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Daughter Approved!!

    Great fit, fun and sporty!! My daughter is begging for more!!

    JEANANNE D.
    Verified Buyer
    Was this helpful?
  • Rated 1 out of 5 stars
    3 months ago
    Beware of using the coupon if you need to return!

    Just a warning for those that use the “welcome” 20 % off coupon. If you use the coupon your items are considered “sale” items and you cannot get your money back if you return the item, you only get store credit. I ordered two different sizes of swimsuits because I wasn’t sure which one would fit my daughter better. Now I can’t get my money back on the one that doesn’t fit just a $70+ credit that I don’t want or need! I read over the return policy before I even bought the stuff to make sure I could return it. It wasn’t on sale so I thought I could get my money back not realizing that after I entered a coupon code at checkout that it made it become a sale item. Just kinda sneaky to me! Not a company I want to do further business with.

    Nita
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Great teen swimsuit

    Fits as described

    Heather G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Great suit for a self conscious tween!

    The adjustable straps are great for a rapidly growing kid

    megan W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    Loved this!

    My tween loved this! Took the fear away of going into the water and let her just be a normal kid hanging out with friends and family at the pool and the lake!

    Farrah E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    A hit!

    My discerning 11-year-old granddaughter loves this suit.

    Elaine C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 year ago
    She loves it!

    My daughter loves this swimsuit!

    Stephanie L.
    Verified Buyer
    Was this helpful?