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Backup for flood daysLiner runs up the back1 / 6Heavy Flow Period Underwear
Heavy Days Trio · 3 pairs
For the days a super tampon isn't enough. A high-waisted brief with a long liner that runs up the back of the seat, made to be the backup layer that catches what gets past, at your desk and through the night.
- Long liner runs from the front up the back of the seat
- High waist that stays put, sizes XS to 4XL
- Wear it alone on lighter days, or as backup under a tampon, cup or disc
- Wear-test it for 60 days. Packs of 3 or more ship free.
Free standard shipping on eligible orders of €50 or more.
Build your rotation
Another pair, same fit.Keep a clean pair ready while another dries.
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Estimated delivery: 6 to 7 business days
Features & fit
- High-waisted brief with a long absorbent liner from the front to the top of the seat
- Four layers: a soft top layer, absorbent core layers and a leak-resistant barrier
- Wear it alone on lighter days, or as backup with a tampon, cup or disc on your heaviest days
- Overnight shorts add coverage for the night. They come in the Full Cycle and Full Week Kits, or on their own
- Sizes XS to 4XL in Noir (black) and Almond (warm beige)
Find your size
- Waist: measure around your natural waist.
- Hips: measure around the fullest part of your hips.
- Between sizes: choose the size that matches your hips. Still unsure? Start with a single; one free size swap comes with every order.
| Size | Waist | Hip | US dress size |
|---|---|---|---|
| XS | 24 to 26 | 33 to 35 | 0 to 2 |
| S | 27 to 29 | 36 to 38 | 4 to 6 |
| M | 30 to 32 | 39 to 41 | 8 to 10 |
| L | 33 to 35 | 42 to 44 | 12 to 14 |
| XL | 36 to 38 | 45 to 47 | 16 |
| 2XL | 39 to 42 | 48 to 51 | 18 to 20 |
| 3XL | 43 to 46 | 52 to 55 | 22 to 24 |
| 4XL | 47 to 50 | 56 to 59 | 26 to 28 |
Wrong size? Every order includes one free size swap.
Product details
The Heavy Days Trio: three high-waisted heavy flow period briefs, two in Noir (black) and one in Almond (warm beige), all in the size you choose. Ships free. Comes with the 60-Day Wear-Test Guarantee and one free size swap.
A Single is one pair. The Heavy Days Trio holds 3 briefs. The Full Cycle Kit holds 3 briefs, 2 overnight shorts and a free wet bag, and the Full Week Kit holds 5 briefs, 2 overnight shorts and a free wet bag. Every pair in a pack comes in the size you choose.
Layers & absorbency
A soft top layer draws moisture away from your skin, the absorbent layers hold it, and a barrier layer keeps it off your clothes and sheets. The liner runs from the front up the back of the seat, where nighttime leaks start.
How much a pair holds depends on your flow. On your heaviest days, wear it as backup under a tampon, cup or disc, and change it as often as you would a pad on the same day. Refer to the garment label for the full fiber composition.
Care instructions
- Rinse in cold water straight after wearing, until the water runs clear.
- Machine wash cold on a gentle cycle, inside a mesh bag or the wet bag.
- Hang to dry. Skip the dryer, fabric softener and bleach, which wear down the absorbent layers.
- Keep 5 to 7 pairs, so a clean pair is always ready while others dry.
Shipping & the 60-Day Wear-Test Guarantee
Free standard shipping on orders of $50 or more. Under $50, standard shipping is $4.95. Express shipping is $9.95, and free on orders of $80 or more.
Orders are dispatched from our fulfilment warehouse within one business day. Delivery to the US takes 6 to 7 business days with standard shipping and 4 to 6 business days with express. For Christmas, order by 14 December with standard shipping or 15 December with express.
The 60-Day Wear-Test Guarantee. Wear it, wash it and wear it again for 60 days after delivery. If it doesn't work for you, email hello@kischt.com with your order number. We refund the pair you wore, with nothing to send back and no return fee. Unworn pairs follow our refund policy.
One free size swap on every order.
kischt heavy flow period underwear
Stop checking the chair.
And the sheets.
When periods turn heavy in your 40s, or fibroids make them unpredictable, a tampon alone stops being enough. This high-waisted brief is the backup layer: a long liner from front to back, a barrier that keeps it off your clothes, and a fit that stays put through a workday and a night.
Sizes XS to 4XL in Noir and Almond, plus overnight shorts for the night.
Liner runs up the back
Backup under a tampon or disc
60-day wear test
Inside the brief
Built for
flood days.
Four layers, and a liner long enough to reach the back of the seat.
Swipe to see more
Side by side
kischt vs
overnight pads.
What changes when the backup is built into your underwear.
| What matters | kischt | Overnight pads |
|---|---|---|
| Where it sits | Built into your underwear | Stuck to your underwear, and can shift |
| Coverage at the back | Liner runs up the seat | Ends where the pad ends |
| On your heaviest days | Backup under a tampon, cup or disc | Often a pad plus a tampon |
| Feel | Underwear, not a pad | Bulky and crinkly |
| After use | Rinse, wash and wear again | Thrown away |
| If it doesn't work | 60-day wear-test guarantee | No returns once opened |
The colors
Two colors.
Plus shorts for nights.
Noir for the heaviest days, Almond for under light clothes.
Sleep through it
Wake up to
clean sheets.
The overnight shorts cover more of the seat, for the nights you'd usually lay a towel down first.
Wear-test it for 60 days. If it doesn't hold up on a heavy day, we refund the pair you wore, with nothing to send back.
Choose your kitGetting it right
Three steps to
your first heavy day.
Start with a pair on a regular day, then trust it on the heavy ones.
Choose by your hips.
Measure the fullest part of your hips and use the size guide. A close fit at the gusset stops leaks.
Pair it on day one.
On your heaviest days, wear it under a tampon, cup or disc as the backup that catches what gets past.
Rinse, wash, hang.
Rinse cold until clear, machine wash cold and hang to dry.
Good to know
Your questions.
Straight answers.
Everything you need to trust it on your heaviest days.
Revisit the comparisonCan I wear it without a tampon?
On lighter and regular days, yes. On your heaviest days, wear it as backup under a tampon, cup or disc, and change it as often as you would a pad on the same day.
Will it help at night?
The liner runs from the front up the back of the seat, where most nighttime leaks start, and the overnight shorts cover more again.
Is it right for perimenopause or fibroids?
Many women with heavy, unpredictable periods wear period underwear as backup. It does not treat the cause of heavy bleeding. If you soak through a pad or tampon every hour for several hours, or pass large clots, talk to your doctor.
Which size should I choose?
Measure your waist and the fullest part of your hips, then choose the size for the larger number in the size guide. Every order includes one free size swap.
How long does delivery take?
Orders are dispatched from our fulfilment warehouse within one business day. Delivery to the US takes 6 to 7 business days with standard shipping ($4.95, free from $50) and 4 to 6 business days with express ($9.95, free from $80).
What if it doesn't work for me?
The 60-Day Wear-Test Guarantee covers you. Wear it and wash it for 60 days after delivery. If it doesn't work for you, email hello@kischt.com with your order number and we refund the pair you wore, with nothing to send back and no return fee. Every order also includes one free size swap. Read the refund policy.
How do I wash it?
Rinse it in cold water until the water runs clear, then machine wash cold on a gentle cycle inside a mesh bag or the wet bag. Hang it to dry, and skip the dryer, fabric softener and bleach so the absorbent layers keep working.