Excellent product, fits true to size.
Bought these for my daughter, she loves them. Keeps her comfortable and prevents any leaks on her heaviest nights.
Great service and great product.
How to make your daughter's first period EASY and FUN!CLICK HERE TO READ.
Welcome to Knicked, Welcome to Puberty and Periods SHOP HERE
Terms & Policies
Please see each product page, for individual sizing.
As a general rule, please choose the same size for our period undies and period swimwear as your child's regular underwear size.
Our period underwear is designed here using Australian Child/Youth underwear guidelines. It's important to note that child sizing, also crosses over into women's sizing at our 12/14, so we have also shown this on our sizing charts (on each individual product page) to assist.
We also understand purchasing online can make judging sizing difficult and everyone has a different body shape (literally hundreds of waist & hip combinations) so we have created guides on each product page to help you choose the best fit for each product, or feel free to email our helpful team at theteam@knicked.com.au with waist & hip measurements so we can assist further.
To measure against existing underwear: use the flat lay measurement (side seam to side seam on the waistband) to compare with their current underwear.
Don't panic if you do find you've ordered the wrong size, KNICKED will happily exchange sizing and also cover the postal costs to reship (once per order) as long as underwear has been tried on over clean underwear and returned in AS NEW condition (not washed/worn free of lint/hair/marks), and packaging in original condition.
Please click here for our Exchange/Refund Forms & Guidelines to organise an exchange.
Knicked Active Stretch™ Period Underwear
Extra Heavy Protection for Active Lives
Extra heavy flow? All-day activities? Super active lifestyle?
We've got you covered.
Our Knicked Active Stretch™ Extra Heavy period underwear is made from breathable, soft micro-mesh stretchy material that moves with you. With ultra heavy absorbency (50mls) and up to 10 hours of protection, these are perfect for active teens and tweens who need maximum protection without the bulk.
💖 What Makes Them Different?
Unlike regular period underwear, our Active Stretch Extra Heavy features:
✔ Extra heavy absorbency (50mls) - equivalent to 7-8 regular pads or tampons
✔ Up to 10 hours of protection
✔ Breathable micro-mesh stretch material
✔ 5-layer construction
✔ Pink waistband (our signature for heavy absorbency)
✔ Cooling, lightweight design
✔ Moves with your body
That means all-day or overnight protection in breathable comfort — no bulky pads, no uncomfortable tampons, just freedom to move even on your heaviest days.
👍🏼 Perfect For:
• Extra heavy flow days
• Sports & active lifestyles
• Overnight protection
• All-day wear
• Tweens & teens on the go
• Anyone who needs maximum absorbency
🌿 Designed for Active Bodies
Created by a mum, designed for real periods.
Our Active Stretch Extra Heavy is:
• Extra heavy absorbency (50mls capacity)
• Reusable & sustainable
• Breathable & cooling
• Stretchy & comfortable
• Made to keep you dry and confident
Because extra heavy periods shouldn't mean sitting on the sidelines.
Knicked period undies have always been and will continue to be FREE FROM NASTIES such as PUL'S (plastics) or PFAS (chemicals).


As a guide: Our teen model wears a size 12-14 in this style and is a ladies sz 8 (waist: 67cm hips: 89cm)
* To measure against another brand of underwear please use the flatlay measurements - side seam to side seam along the waistband.
Tracked postage is $9.95
Express postage is $14.50
Orders over $99 receive complimentary FREE REGULAR SHIPPING
Knicked will exchange item(s) that have not been washed, worn and are in AS NEW condition, we request you submit our Exchange Form within 14 days of receiving your product. Knicked will cover one new shipping cost as a gift to assist - please note: if purchased on sale or outside Australia item(s) can ONLY be returned for a gift voucher to repurchase a new size or style within 5yrs.
Excellent product, fits true to size.
Bought these for my daughter, she loves them. Keeps her comfortable and prevents any leaks on her heaviest nights.
Great service and great product.