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Everything they need. All in one kit. Everything they need. All in one kit.

You can't predict her first period. You can prepare for it.

Shop All First Period Prep Get the First Period Kit

Free period undies when you spend $120

Your leakproof questions, answered.

What is Leakproof underwear and how does it work?

What do the different underwear absorbency levels mean?

Ultra Absorbency

Absorbs the equivalent of 7-11 super tampons. Our longest front-to-back liner, designed for their heaviest flow days and overnight protection.

Heavy Absorbency

Absorbs about the same as 4-7 super tampons. Perfect for overnight protection or your teens heaviest days when changing into a fresh pair might not be convenient.

Moderate Absorbency

Absorbs about 2.5 super tampons' worth of blood. Ideal for medium period days, discharge and sweat.

Light Absorbency

Absorbs about the same as about 1 regular tampon worth of blood, sweat or discharge. Ideal for lightest period days, spotting, sweat and discharge.

How does period swimwear work?

Our period swim bottoms have a triple-layer gusset that absorbs your flow and locks in leaks, in and out of the water. And when you throw them in the wash with detergent, everything releases through the top layer so your swimwear comes out fresh and clean. Your other clothes will be totally fine too, we promise.

Here's how the three layers break down:

Layer 1 is a silky-smooth top layer that sits right against the skin.
Layer 2 is a super absorbent middle layer built with our leakproof tech that holds up to 1–3 tampons worth of blood.
Layer 3 is a waterproof outer layer that prevents any leaks from showing through.

How do I wash period underwear?

It's easy, we promise. Give them a quick rinse under cold water first, then toss them in the washing machine with your regular clothes, cold water, mild detergent, no softener or bleach. For drying: lay flat for medium absorbency styles, or tumble dry on low for high and super absorbency ones. That's it. No ironing needed!

Does my teen need to wear a pad or tampon with period underwear?

Totally up to them! Every flow is different, and there's no wrong answer. Depending on the absorbency level and how heavy their period is, they can wear KT undies on their own or use them as backup alongside a tampon or menstrual cup. Whatever makes them feel most confident is the right call.

Super Leakproof® Mini Sleepover Boxer

$45.00 USD

SuperPlus Leakproof® Sleepover Short

$45.00 USD

Super Leakproof® Mini Sleepover Boxer

$45.00 USD

Light Leakproof Cotton Bikini Underwear

$22.00 USD

Light Leakproof Cotton Bikini Underwear

$22.00 USD

THEY WORK

Over 2M+ pairs sold prove it.

Kt Period Undies don’t just work—they work better than you’d expect. Washable, discreet, and super comfy, our undies keep you feeling fresh and confident. So tell your tween to RSVP yes to that sleepover and wear that white tennis skirt. She's covered.

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Totally Not TMI

Kt Period Playbook Kt Period Playbook

There’s zero shame in teens wanting confidence, not confusion when it comes to periods.
That’s why we made this free guide and workbook just for them.

Get Your Free Digital Copy

TRY THEM RISK FREE

First Pair Risk-Free Policy

You can try one pair from your first order risk-free for 30 days! If you ordered the wrong size of period underwear, we’ll send you a different pair at no cost or offer you a standard refund within 30 days of delivery.

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