Name: Leakproof Bikini Underwear
Brand: proof.
SKU: PFBI2000SND:XS
Price: 39.0 USD
Availability: InStock

Holds

up to 4 Tampons or 8 Tsps

AbsorbencyHolds up to 4 Regular Tampons or 8 Teaspoons

Color Sand

Black

Sand

Navy

Wine

QTY

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Stay Dry Comfort Bra

Finally, a bra made for boob sweat!

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Classic, cute, and super absorbent, our Bikini style underwear keeps you leak-free and confident.

With a high leg opening, some of our highest leak coverage and a mid-rise fit, our Bikini is made for breathable, waterproof protection. Created with our multi-layer Leak-Loc™ system, this undie draws moisture away from the body, keeping you dry all day.

Full Lining

The Bikini offers total front-to-back leak protection. Our revolutionary leakproof core spans from the front waistband to the back waistband for complete leakproof coverage.

Great for

heavy periods

moderate bladder leaks

replace a pad

replace or back up a tampon or cup

sweat

odor reduction

Outer: 75% Nylon 25% Spandex

Lining: 100% Cotton

Lining: 100% Polyester

Lining: 69% Cotton 25% Polyester 6% Acrylate

Protection

Full Lining

The Bikini offers total front-to-back leak protection. Our revolutionary leakproof core spans from the front waistband to the back waistband for complete leakproof coverage.

FAQs

See all FAQs

The bikini undies by Proof feature a mid-rise fit, high cut leg opening, and moderate booty coverage, all in a comfortable stretch fabric that moves with your body.

The bikini features a high-leg opening and narrow sides, with a mid-rise and moderate back coverage. The brief is designed with wider sides, lower rise, and moderate back coverage.

The leakproof bikini by Proof is perfect for heavy periods. It holds up to 4 regular tampons - that’s 8 tsp! - of liquid, making it perfect for all-day or overnight wear. The bikini is also equipped with front-to-back leakproof protection for extended coverage.

Proof undies are designed to be better for you, and the environment! Single-use plastic period products like tampons and pads end up in landfills and oceans, where they pose a serious threat to wildlife. By switching to Proof, you help to reduce single-use plastic waste.

Don't just take it from us, hear why real women love Proof...

See The Proof

Proof’s patented Leak-Loc™ technology protects against all of life’s leaks, both big and small. Our undies hold up to 10 teaspoons (that’s 5 full tampons worth!) of liquid.

Explore Our Technology

This is really (really) leakproof underwear

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Best Invention Ever

I’m extremely surprised by how well this works! I have very irregular periods, and they can sometimes be very light and other times very heavy. With these undies, I don’t worry about staining or leaking. I wear them for 11-12 hours on my heavy days and they have worked great!

I also love how they wick moisture away from you, so you can feel dry all day. The first time I wore them and tested them around the house, I was able to relax and forget I was even on my period! They are also very easy to wash, though you need to leave them for several hours to air dry. Once you put them on after drying, they conform to your body, so they don’t lose their shape.

I love that it’s like wearing a diaper, except they are far sexier than a diaper! They don’t look different from regular panties and they don’t even leave panty lines under your clothes.

I still use pads for when I’m letting the undies air dry, but I plan to purchase another pair or two so I can rotate them and never have to wear pads again. When you consider how well they’re made, how effective they are and the fact that they’re washable and reusable, you find they’re really not expensive at all. At least I consider the price totally worth it for the peace of mind and comfort it gives me.

Run Small

I bought several different types of undies from Proof. All we’re size large and fit great except for these. This one fits so differently. Almost like two sizes too small. I can wear it but it’s not super comfy and has zero stretch. Even if I sized up, not sure I’m a fan of this cut/style. Still a fan of Proof though!

Comparing to competitors

I own a cheap bamboo set from Amazon and Thinx:

Thinx super hip hugger

Thinx air hiphugger

Thinx supper cotton brief

I am 47 years old with a 8,6,3 & 1.5 year old. I am old. But I love period panties. I cannot wait to be able to offer more options to my daughters than I was offered when I started my period. I have a pretty heavy period for like 7 days so I am still figuring this out. I have owned my thinx for a year. I won a sweepstakes on Proof. I am very impressed with proof. I would like to try the heavier period panties as these were a heavy not a super heavy. After the birth of my 5th child I have a little bit of uterine prolapse and my menstrual cup is no longer comfortable.

Proof has a more swimwear feeling than the thinx.

By swimwear its a more rubberized fabric but not like neoprene and very silent.

Proof dries more quickly when air dried than thinx

the wrap of the fabric around the crotch zone is nice as it shows the fluid moving towards clothes more easily to let you know its time for a swap.

Thinx does not have a sound but I think a friend touched my panties and threw them in the dryer and they had a noise level to one pair. Noise not more than pants sounds but had a microphone been near my netherlands it might have a slight paper sound on that pair.

I am happy to promote period panties and love this product.

Once you go Proof…you’ll never go back!

For the past 2-3 years I’ve wanted to be done with pads and tampons. Let’s face it, they are ancient and with all the new technology, there is no reason to hold on to them. Yet, every alternative that I researched kept missing the mark. Don’t even get my started on those cups okay. I’ve been wanting to try the leakproof underwear but I wasn’t convinced they would give me what I was looking for. Yet, every cycle I grew more and more in my disdain for products that I would wear panty liners and layer my underwear and clothing just to avoid the bulkiness and discomfort of pads and tampons. Simply put I wanted to feel free. I researched the leakproof underwear again and decided to give it a try. I started with two because the prices were $30-$35 (moderate and heavy flow options) and I didn’t want to waste money on something that didn’t work. Listen!!! This purchase exceeded my expectations. The panties are comfortable, stretchy and secure. The absorption is unbelievable. I feel completely liberated! It’s magical. They feel better than my regular underwear. I will never go back to living in the Stone Age!! I went 6-7 hours in each and there is no wetness, no odor, no residue. NOTHING. Looks and feels like a fresh pair of underwear! I got a size medium and I have a lot of booty but it covered my backside. There was no bunching or wedging. Now that I know they work I recommend buying at least 4 but y’all need to have some discounts. Buy 3 get one free…

Leakproof Bikini Underwear