Choose Your Pool Perfect Combo
Choose Your Pool Perfect Combo

PERIOD STRESS AT SWIM SQUAD, A MEET OR THE BEACH? Hard pass.
UnderSwim OG is period swim underwear worn beneath full-bottom swimwear. It period-proofs the swimsuit she already owns without adding bulky seams or an obvious periodwear silhouette.
Its integrated protection absorbs up to 20 ml of menstrual flow, around four regular pads’ worth, while a sealed, impenetrable barrier locks flow in and helps keep pool or sea water out.
The seamless OG fit disappears beneath training swimmers, race suits and regular-coverage bikini bottoms. Menstrual protection: handled. Awkward outlines: not invited.
OFFICIAL PERIOD-SAFE SWIM UNDERWEAR OF SWIMMING AUSTRALIA.
UnderSwim is compliant for USA Swimming Age Group Competitions under Rule 205.10.1. Period underwear is also permitted under Swim England guidance for training and eligible Swim England competitions, subject to the applicable event rules.
- Reusable period-proof swimwear layer worn beneath full-bottom swimwear
- Up to 20 ml absorbency, around four regular pads’ worth
- Seamless, no-show OG fit
- Water-resistant outer coating and chlorine-resistant performance fabric
- PFAS-free and OEKO-TEX® STANDARD 100 certified for safety
- Girls’ sizes G10-12, G12-14 and G14-16
- Women’s sizes W10-W18
- Black, Neutral and Navy
Water blocked. Period locked. Swim still happening.
$36.95

<p><strong>PERIOD STRESS UNDER A HIGH-CUT SWIMSUIT? Hard pass.</strong></p><p>UnderSwim G-Fit is period-proof swim underwear designed to disappear under high-cut swimsuits, racing suits and bikini bottoms.</p><p>Its seamless high-leg cut gives her a discreet layer beneath the swimwear she already wants to wear.</p><p>Up to 15 ml absorbency is around two tampons’ worth of protection, without bulky seams or a waterlogged feel.</p><p>A water-resistant outer helps keep pool and sea water out. Four thin absorbent layers lock menstrual flow in. No wet-nappy energy.</p><ul><li>Invisible under high-cut swimwear, including one-piece, racing and bikini styles</li><li>Seamless high-leg fit in Black or Neutral</li><li>Up to 15 ml absorbency, around two tampons’ worth</li><li>Water-resistant and chlorine-resistant</li><li>Compliant with Swimming Australia’s Inclusive Swimwear Policy</li><li>USA Swimming compliant for Age Group Competitions under Rule 205.10.1</li><li>Swim England compliant</li><li>PFAS-free and OEKO-TEX® STANDARD 100 certified for safety</li><li>Girls’ sizes G10-12, G12-14 and G14-16; women’s sizes W10-W18</li></ul><p>UnderSwim G-Fit is the discreet period layer for swimmers who want the protection underneath and the swimwear on show.</p>
$36.95
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YOUR SWIM. YOUR WAY. THREE PAIRS, BUILT BY YOU.
Build a three-pack of UnderSwim period swim underwear and choose the fit, size and colour combination that works for her swimmers and her week.
Go with three UnderSwim OG pairs. Choose two OG and one G-Fit. Or build another mix from the available UnderSwim options.
OG is designed to disappear beneath full-bottom swimwear. G-Fit gives a higher-cut option for higher-leg swimwear. Both add reusable period protection beneath the swimsuit she already owns.
TO BUILD YOUR COMBO:
- Choose three UnderSwim pairs.
- Select the fit, size and colour for each pair.
- Select Add Bundle to Cart.
Three-pack value. Zero sitting out.

3 SIMPLE STEPS
HOW TO WASH
STEP 1. RINSE
Rinse worn undies in luke warm water until water runs clear. It's best to do this ASAP.
If that's not poss, pop them in a Stash Bag and take them out at home (before they dry out!) and rinse.
STEP 2. MACHINE WASH
Toss 'em in the wash, cold cycle with stuff of similar shades.
Skip the fabric softener - bamboo's already got the softness nailed and the absorbent layers aren't a fan! For that extra bit of care, a wash bag is your undies' best friend. 🧼💖
STEP 3. HANG OUT
... not with the undies - that'd be weird!
Pop underwear out on the line to dry naturally. No dryers, please. And make sure your underwear is fully dry before storing them away.
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