Home/Scarlet Period | Made for a Super Light Flow/Sultry Days Set
Scarlet Period The Sultry Days Set | Period G-String & Invisible Thong
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch
Scarlet Period The Sultry Days Set | Period G-String & Invisible Thong
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period G-String | Leakproof, Light Absorbency, PFAS-free, Organic Cotton
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch
Scarlet Period Invisible Thong | Like a panty liner, PFAS-free, Soft with 360° stretch

Sultry Days Set

Tight pants. Light flow. Sorted.

$36.00 $42.00

Two slinky, seamless styles for your most confident days, with quiet protection from spotting, sweat and discharge.

    Chemical-free (no PFAS!)
    Save $$ with Sets
    Stylish and ultra-flattering fit
    Stylish and ultra-flattering fit
Scarlet Period G-String (Light) (Size)
Scarlet Period Invisible Thong (Super Light) (Size)
Scarlet Period Invisible Thong (Super Light) (Color)

The Set for Sultry Days has two ultra-discreet bottoms designed for comfort, coverage, and confidence - no matter your flow. Both styles feel like your comfiest undies - lightweight, soft, and irritation-free.

⭐ Light Absorbency Period G-String: Holds up to 3 teaspoons (2 tampons) in breathable, GOTS-certified Organic Cotton that’s PFAS-free.

⭐ Invisible Thong: Ideal for spotting and discharge with a seamless, second-skin fit. Choose between classic Black or Nude for a sleek, go-with-everything staple.

✨ Rinse in cold water until clear.

✨ Machine wash cold with mild detergent.

✨ Skip bleach and fabric softener - your bikini brief doesn’t need them.

✨ Line dry or tumble dry on low. Simple, right?

⭐ Period G-String: 95% Organic Cotton, 5% Spandex, and a Polyester/PUL Quick Dry Gusset.

⭐ Invisible Thong: 76% Polyamide, 24% Elastane, and a Polyester Quick Dry Gusset.

All Scarlet underwear is free from added chemical treatments, including PFAS (independently lab tested).

✨ Fit Note: Our underwear runs on the slightly smaller side - if you're between sizes, size up.

✨ Teen-to-Adult Fit: Our sizing is unique - please refer to both the numerical (e.g. 10, 12) and letter sizing (e.g. M, L) in our guide.

✨ Australian Sizing: We use AU sizes - international customers, check our Size Guide.

✨ Still Unsure? Contact us for advice. We love a chat!

Did you know that over 12 billion pads and 7 billion tampons end up in landfills yearly? By choosing Scarlet, you're supporting a more sustainable future - where self-care and sustainability go hand in hand.

✨ High-Quality, Safe Fabrics: Made with care, free from PFAS and harmful chemicals, and independently lab-tested for your safety.

✨ Eco-Conscious Manufacturing: Crafted with a focus on quality and reducing environmental impact.

✨ Recyclable Packaging: Minimal waste for a cleaner world.

✨ 1% for the Planet: Scarlet is proud to contribute to environmental stewardship with every purchase.

Size Chart

Size chart for Sultry Days Set
Scarlet Period The Sultry Days Set | Period G-String & Invisible Thong

Sultry Days Set

$36.00 $42.00
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For a light flow, Scarlet Period Thongs and G-Strings are a great match

Like Wearing Nothing At All

Two ways to go barely there. One leak-proof promise.

Meet the power couple of period-proof undies: our classic G-String and ultra-discreet Invisible Thong. No VPL. No stress. Just undies that have your back(side).

  • Keeping VPL at bay throughout your bleed
  • Mid-rise, minimal bum coverage
  • No PFAS, no weird chemicals
  • Invisible under anything, including your tightest jeans
BUY NOW

Your Questions, Answered

How do they work?

Scarlet Period Underwear is designed to fit like normal underwear and features multi-layered leak-proof technology that wicks away moisture, absorbs fluid, and contains it to keep you dry and protected. 

The built-in leak-proof technology is harder working than disposable pads which means it can safely hold more liquid and last for years not hours. Loved by all; you can read some reviews.

Do I need to wear a cup, tampon, or pad too?

Depending on the absorbency you choose and the heaviness of your flow, you can wear our period undies on their own or as backup along with a Period Cup or tampon.

What does the absorbency level mean?

Super Light: Holds up to 1 teaspoon, equal to less than one regular tampon. Think of it as a new-age panty liner, great for spotting, light leaks and discharge. Try: Invisible Thong

Light: Holds up to 3 teaspoons, equal to 2 regular tampons or one pad. For light days, drips and discharge. Try: G-String or Bikini Brief in Light-Moderate

Moderate: Holds up to 5 teaspoons, equal to 3 regular tampons or 2 pads. For moderate days, or as extra defence on heavy days with our Period Cup. Try: High-Waist Brief or Bikini Brief in Moderate-Heavy

Heavy: Holds up to 7 teaspoons, equal to 4 regular tampons or 3 pads. Our heavy hitters are great worn on their own, day or night. Try: Boyshort or Period Cup

How do I wash them?

After use, rinse them in cold water (we recommend in the shower) until they run clear. Then, machine wash in cold water with mild detergent (no bleach!). Try our Laundry Bag to safeguard them on laundry day. Then just hang out to dry (the sunnier the better) or tumble dry on low - that’s it!

TIP: If it’s your first wear, pop them in the washing machine with your next cold cycle - washing them before wearing activates their absorbency even more.

What is your 30-day risk-free trial?

We offer a 30-Day Risk-Free Trial for first-time shoppers for one pair of underwear. If you’re unsatisfied or have sizing concerns, email us at support@scarletperiod.com.

How do I pick the right size for me?

We get it, sizing for bottoms is anything but standardised. Which is why this size guide will help break it down for you. Make sure to check both our numeric and letter sizing so no confusion (ie. our large is a 12).

When in doubt, feedback tells us better to size up. Still confused? You can also email us for help at support@scarletperiod.com.
★★★★★

"A surefire way to ensure you make mindful, sustainable choices that are good for you and the world you live in."

- STYLE magazine

★★★★★

"These g-string undies made from organic cotton have a mid-rise silhouette with minimal bum coverage."

- Refinery29

★★★★★

"My personal favourite is its G-string - it’s ultra cute and comfy, perfect for lighter days."

- LifeHacker

Real advice for real cycle days