Name: The Core Duo
Brand: Tweak
Price: 59.98 AUD
Availability: InStock

New-Core duo

In stock, ready to ship
Backordered, shipping soon

Meet Your New Power Couple.

Why choose when you can have the best of both worlds? The Core Duo puts your essential black front and center. This bundle delivers 1 x Onyx (The Essential Black) and 1 x Bare (The Invisible Nude) in our upgraded, high-performance fit.

We’ve leveled up the comfort with a wider waistband that stays put and a longer triangle cut designed to sit higher on your hips for a flattering, leg-lengthening silhouette.

Stay Fresh: Signature moisture-wicking bamboo gusset.
Stay Dry: Breathable Coolon™ fabric pulls sweat away fast.
Perfect Fit: Available in sizes XS – XL.

🚚 Shipping & Delivery

💌 How Much Is Shipping?

We keep it simple and speedy:

Australia: $10 flat rate with Australia Post or trusted local couriers

Everywhere else: Is calculated at checkout based on your location (because your booty deserves premium delivery)

⏳ When Will My Order Arrive?

We hustle hard to get your order out fast:

Within Australia: Usually lands in 3–5 business days

International: Up to 14 days depending on where you are in the world

Heads up: Global shipping’s still a little funky post-pandemic, so a few delays may pop up here and there. We appreciate your patience (and your excellent taste in underwear).

📦 Will I Get a Tracking Number?

You bet. As soon as your order ships, we’ll ping your inbox with tracking info.

Didn’t get it? Hit us up at support@tweakmeonline.com.

Pro tip: All parcels come with authority to leave—so if you’ve got specific drop-off instructions, let us know at checkout.

No PO Boxes, please. Make sure your delivery address is attended during business hours.

🚛 Which Courier Do You Use?

Australia: Australia Post or a local courier service

International: We choose the best based on your location.

💸 Will I Pay Extra Taxes or Duties?

If you’re shopping from outside Australia, local customs fees, import duties, and taxes may apply. These aren’t charged by us, so check with your local customs office if you're unsure.

Any questions? Don’t hesitate—drop us a line at support@tweakmeonline.com.

Your order’s in good hands—and soon, your cheeks will be too. 😉

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Why You'll Love Tweak:

✔ Stay Fresh & Dry Moisture-wicking bamboo gusset keeps you cool.
✔ Breathable & Quick-Drying Coolon™ fabric pulls away sweat fast.
✔ No Chafing, No Slipping Seamless construction for a second-skin feel.
✔ Soft & Secure Fit Flexible, no dig waistband.
✔ Invisible Under Clothes Say goodbye to VPL.
✔ Durable & Long-Lasting Withstands hundreds of washes without losing shape.

Let customers speak for us

from 254 reviews

Really informative and easy to digest

Really informative and easy to digest. A good way to kick start my way to better habits.

Rach Larkins

12/14/2025

Tweak 4 Week Transformation - EBook

My wife's new favorite underwear for workouts

I purchased a pair for my wife to try before purchasing multiple pairs.

She says these are her new favorite for working out and runs. The construction is top notch. She says they are very comfortable and better than most g-strings and athletic underwear she has tried. We are both underwear aficionados, and we recognize that the quality exceeds other premier athleisure underwear brands. We will definitely be purchasing more. They truly are seamless and comfortable. No VPL whatsoever.

Anonymous

12/09/2025