NuStretch Brief - One Size


In partnership with experts in microfibre technology, our new patent-pending one-size underwear is made using our revolutionary NuStretch® fabric, stretching across multiple sizes and moulding to every body type, while retaining stretch perfectly. Our reliable built-in leakproof tech absorbs all life's leaks — from periods to incontinence. 

Our patent-pending design is perfect for changing body sizes and gives you confidence through periods, incontinence, and post childbirth. Our breakthrough seamless material is not only comfortable, but it's also soft, breathable, and guarantees no VPL.

Available in two sizes:

One fits sizes UK 6-14, One+ fits sizes UK 16-30

  • Perfect first-time fit guaranteed
  • NuStretch ® fabric — moulds to every body
  • Super absorbent — perfect for moderate to heavy flows
  • No VPL — soft, breathable, and seamless design
  • 100% leakproof — wear for up to 12 hours
  • Reusable and washable — eco-friendly protection
  • Certified vegan and cruelty-free
Next day delivery available
Easy returns within 60 days
Free shipping on UK orders over £30!

Our period-proof underwear combines cutting-edge technology with ultimate comfort. Here’s how it works:

Multi-Layer Protection: Our underwear features a unique multi-layer system designed to keep you dry and comfortable all day.

  1. Moisture-Wicking Layer: Quickly draws moisture away from your body to keep you feeling fresh.
  2. Absorbent Core: Locks in fluid, providing reliable protection against leaks.
  3. Leak-Resistant Barrier: Prevents any leaks, so you can move with confidence.
  4. Breathable Fabric: Ensures airflow to keep you cool and dry.

Machine wash max 40°C with mild detergent, hang to dry. No bleach. No tumble dry.

BODY: 95% Organic Cotton, 5% Elastane
GUSSET LINING: 95% Organic Cotton, 5% Elastane
GUSSET:100% Microfibre, Biodegradable TPU

Our underwear has no added PFAS, and has been successfully tested for harmful substances and certified according to STANDARD 100 by OEKO-TEX®️.

Learn more about how to care for period underwear.

UK Bound? Lucky You!

Enjoy free shipping on us, on all UK order over £30! Need it quick? Pick next day delivery at checkout.

Order before 12:00 pm GMT on a working day (that’s Monday to Friday), and we’ll send out your goodies on the same day. Talk about speedy service!

Not in the UK?

No worries! We’ve got free worldwide shipping on orders over £75. Plus, you can speed things up with express shipping options at checkout.

Returns Made Easy

Didn’t hit the jackpot with your purchase? No sweat! We’ve got your back with hassle-free returns and exchanges for 30 days. And if our products don’t live up to the hype (spoiler: they totally will!), we’ll refund you within 60 days*. Yep, we’re that confident! 🚚✨

* Try fluxies risk-free on your first order. If our undies don't work as promised, let us know within 60 days and we'll refund you. The 60-day risk-free trial applies to one worn pair of undies only.

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NuStretch technology

Our patent-pending NuStretch undies are the world's first seamless, one-size leak-proof underwear designed to adapt to every body perfectly, while retaining shape and stretch.

Feel: buttery soft

Stretch: up to 400%


Breathable and ultra-soft


Reusable and washable


100% leakproof for up to 12 hours


fresh and dry odour control

Comfort, uncompromised.

Your questions, answered.