UnderLiner: Built-In Backup for Just-in-Case Situations













Description
UnderLiner is like a reusable, more absorbent version of a traditional pantyliner — built right into her underwear. No bunching. No slipping. No landfill. Perfect protection during first whispers of a new cycle and when it's on its way out, as well as for security during the pre-period plot twists like awkward spotting and vaginal wetness.
She won’t notice it’s there. But she’ll love knowing it is!
Material
95% Cotton / 5% Spandex
Wear and Care
Rinse after wear. Do not allow period underwear to dry with blood in the lining, it causes them to become brittle and potentially ineffective.
If you're unable to rinse straight after wear, pop them in a wet pouch until you can.
Machine wash, no hotter than 30 degrees. No do use fabric softener.
Hang to try. Tumble dryers are a no-go zone. Again, they mess with the absorbency.
Want to know more? Here's our full Wear & Care page.
Returns/ Exchanges?
We want you to love your Eltee Sydney purchase, but we understand that sometimes things don’t work out—and that’s okay!
There are a few conditions, but not many:
- In original condition unworn and unwashed, and returned within 30 days.
- Swimwear and underwear must have their hygiene seal in place and underwear must be returned in its packaging as new.
To return or exchange an item, simply head to our Returns & Exchange page.

Built-in backup she can wear every day.
Clean, second-skin comfort and discreet protection she can wear every day.
UnderLiner looks and feels like her regular undies, but hides a superpower: ultra-thin absorbency that catches those early surprises—think spotting, discharge and other pre-period plot twists.

HOW UNDERLINER WORKS
Think pantyliner. Now make it smarter.
UnderLiner is made for the lighter, earlier days of her cycle — spotting, discharge, and those "is it starting?" moments.
It's ultra-thin protection that feels like regular undies but catches sneaky surprises before they cause any drama.
Disposable pantyliners can slip, bunch, and need changing often. UnderLiner is part of her undies — reusable, breathable, and (way) more absorbent.
No waste. No hassle. Just everyday backup she can wear without thinking about it.
UnderLiner is perfect for pre-period discharge, spotting, or very light flow at the start or end of a cycle.
For heavier period days, we recommend our Bumpers Briefs instead — they’ve got a higher absorbency level and our exclusive leak-locking Bumpers technology.
UnderLiner offers light absorbency (same as 1-2 regular pads). They're light and comy, just like regular undies, but they do the heavy lifting of 4 panty liners — think spotting, discharge, or the first/last light days of her period.
Yep! UnderLiner is comfy and breathable enough for daily wear — perfect for those "just in case" school, sport, or hanging out with mates days when her anxiety around changing or leaking might hijack for focus and her fun.

LIMITED FIRST RUN STOCK
We made UnderLiner after hearing girls wanted a safeguard — not a full period brief, just backup they could wear every day.
We’ve only made a small first run to see if it hits the mark.

UnderLiner is true to size > skews large. If it between two sizes, we recommend that you size down.
WAIST: Around belly button (narrowest part of torso).
HIP: Measure the fullest part of your bottom around to the top of your public bone.
1/2 MEASURE: Lay a pair of similar underwear flat and measure the front.