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Home / Swim One-Pieces / Leakproof Classic One Piece Swimsuit

Leakproof Classic One Piece Swimsuit

$118.00 USD

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Our #1 selling one-piece

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Built-in leak protection

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Premium UPF 50+ fabric

| Black
| Black
| General
| Black
| Black

Absorbency: Light

Light
Drop
Drop
Drop
Drop
Drop
about 1-3 regular tampons
Essential
Drop
Drop
Drop
Drop
Drop
No Absorbency

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. Once an order is placed, we cannot guarantee any address updates, order changes or cancellations. Orders placed on Friday after 1PM will not be shipped until the following Monday.


Split Shipments

Most orders will ship from a single warehouse. However, we occasionally ship from a combination of warehouse locations, so you may receive your order in multiple parts. If items from your order ship in separate packages, we’ll send you tracking information for each package when it becomes available.

Delivery Timelines

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines do not include processing times. See above for details. All transit times are measured in business days which are Monday-Friday, excluding holidays.

Please note, all shipping timelines are estimates and are not guaranteed.

We are not able to ship to US territories (including Puerto Rico, U.S. Virgin Islands, Guam, Northern Mariana Islands and American Samoa) at this time.
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.

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.
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"Brilliant for unexpected spotting."

- Oprah Daily

Classic Style

A fit we've spent years perfecting.

Sun-Smart Protection

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

Worry-Free Protection

Discreet, built-in protection that absorbs about 1 regular tampon worth.

Feels Made For You

Thicker, adjustable straps make it adaptable for different sizes and torso lengths. It features a shelf bra with removable cups and full bum coverage.

Zoom

| Black
| Black
| General
| Black
| Black

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

The 3-layer liner absorbs and locks in leaks, whether you're in or out of the water. When washed with detergent, blood releases through the top layer for a fresh, clean suit.

Soft Top Layer

Top Layer

A silky-smooth top layer that feels just like a regular swimsuit.

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4.6
Rated 4.6 out of 5 stars
Based on 178 reviews
Total 5 star reviews: 145 Total 4 star reviews: 14 Total 3 star reviews: 10 Total 2 star reviews: 3 Total 1 star reviews: 6
92%would recommend this product
ComfortRated 4.8 on a scale of 1 to 5
FitRated 0.1 on a scale of minus 2 to 2
SupportRated 4.4 on a scale of 1 to 5
EffectivenessRated 4.6 on a scale of 1 to 5
Ease of UseRated 4.7 on a scale of 1 to 5
Write a Review (Opens in a new window)
178 reviews
  • Rated 5 out of 5 stars
    21 seconds ago
    Great fit

    I love this bathing suit and was pleasantly surprised at how well it fit! Got my normal swimsuit size. I'd prefer a little more lift but it's very nice for being a one-piece. Got it at a major sale price so even more worth it.

    Dayna E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 hours ago
    The most flattering swimsuit

    Bought this swimsuit last year in another colour and received so many compliments Thats I bought it again when on sale.

    Karin W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Comfortable swimsuit

    Feel comfortable and confident

    LIEZEL J.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Gorgeous color

    Beautiful colour and nice fit. I like that it is a comfortable suit with great coverage for a layabout day on the beach

    Catherine M.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    5 Stars

    5’ 8.5”-135 lbs-Size M-To me this swim suit feels luxurious. The lining feels beautiful against my skin. Extremely pleased.

    Christine
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Fabulous Fit!

    A super fit. Classic style. Beautiful fabric.

    Jayne B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    I love this suit!

    As a mom of two small kids, I LOVE this suit. It is so comfortable, flattering and I feel so great in it. Highly recommend!

    Mary C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Great Suit

    Nice suit, does the job

    Shari L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    classic one piece swimsuit

    This swimsuit is so comfortable and nice to have on for a lot of the day.

    Erika H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    The fit

    Great fit.. covers bum well, I like the feel of the suit

    Janet M. S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    Classic one piece swimsuit

    This is the best bathing suit I have ever bought.

    Darlene R.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    It very comfortably

    It was much better than I can go swimming

    Mckenzie F.
    Verified Buyer
    Was this helpful?