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

Teen Period Swim Square Neck One-Piece

$99.00 CAD

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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 Timelines

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* CAD = Free Shipping (2-6 business days)

Orders under $100* CAD = $12 CAD Shipping (1-3 business days)

Orders delivering to NWT, Nunavut and Yukon are subject to $20 delivery fee.

*After discounts, before shipping and taxes.
Easy Returns within 30 Days

Returns

Returns

Sale & Last Call

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

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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.
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Product Description

Enjoy swim days with confidence, even on your period, with the Teen Period Swim Square Neck One‑Piece, a leak‑fighting moderate‑absorbency swimsuit that absorbs about the equivalent of 3 regular tampons, features a sporty square neckline with built‑in shelf bra and removable cups, and is crafted from premium UPF 50+ fabric that protects your skin while you swim or play in the sun — fully machine‑washable with discreet built‑in protection that looks and feels like regular swimwear.

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.

Sun-Smart Protection

UPF 50+ fabric protects your skin while you soak up the sun.

Zoom

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

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
  • 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
  • • Daily freshness. For sweat, discharge, period spotting, or backup protection.
  • 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
  • • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
  • 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
  • • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
  • 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 these products
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
    2 months 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
    3 months 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
    5 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
    5 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 5 out of 5 stars
    5 months ago
    Daughter Approved!!

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

    JEANANNE D.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    6 months ago
    Great teen swimsuit

    Fits as described

    Heather G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    6 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
    6 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
    7 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?
  • Rated 5 out of 5 stars
    1 year ago
    Great swimsuit

    Bought it for my daughter who is swimming competitively. Provided great protection and she swam comfortably.

    True to the size. It would be great if there were more design and color options z

    gizem e.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 year ago
    Perfect

    We love this bathing suit. Perfect for swimming when you’re on your period and feeling confident while you’re wearing it!

    Reiko K.
    Verified Buyer
    Was this helpful?