Flak Sack II Flak Sack II Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II
Flak Sack II

Flak Sack II

623 reviews
Regular price $169.00 USD Save $-169.00 USD

558 in stock

The Flak Sack II is a super tough theft-resistant drawstring backpack. Made from Flaknit, our proprietary slash-resistant fabric, this bag achieves an ANSI A9 cut level, the highest there is! If you simply don’t want to settle for anything but the best, the Flak Sack II is there for you, no matter what the world throws at you.

  • Flaknit™ virtually slash-proof fabric achieves A9 cut level, the highest there is for slash, tear, abrasion resistance.

  • Patented double steel reinforced locking strap & heavy-duty combination lock allow you to lock the bag shut, and to a fixed object.

  • Cut resistant ropes prevent strap slashing

  • Large fleece lined interior RFID blocking pocket shields unauthorized scanning

  • Sternum Strap keeps ropes centered across chest 
    • 18" x 14" (fits Macbook Pro 13 inch)

    • Capacity: 13 litres

    • 2 lbs (includes lock)

    • Interior Pocket: 10" x 8" (can fit an iPad Mini)

    • Natural leather patch & accents

    • Designed in Columbus. Manufactured in China. Proprietary fabric design & developed in the USA.

For Domestic shipments (USA & Canada), we offer free shipping on all orders over $75. Shipping typically takes 4-7 business days. For international orders, shipping cost will vary depending on the country. Any taxes, duties, or customs fees owed are the responsibility of the customer. Please be aware of your country's customs duties before purchasing. Shipping costs are non-refundable. Delivery can take up to 12 business days depending on location and can vary more due to COVID-19 delays.

Flak Sack II

Our Toughest Theft-Resistant
Drawstring Backpack

How it works

Cinch it, Pull it, Lock it, Leave it. It's that simple. This is the bag that everybody, at some point in their life, wishes they had. Elegant in its simplicity and unapologetic in its effectiveness. Sometimes you just need a safe place to put your personal items and valuables while you focus on something else.

Steel Reinforced Locking Strap

Solid Brass Combination Lock

Slash Proof Fabric - A9 Cut Level

Stab Proof Side Seams

Slash Resistant Drawstring Ropes

Secure Sternum Strap

man wearing anti theft backpack while hiking

Flagship Anti-Theft

We scour the globe to find the best and most technologically advanced materials and manufacturers available. We compromise on nothing when it comes to quality and authenticity, and cut no corners in crafting goods built to outlive their owners.

Designed to Protect,
Built to Last

Doing the daily commute, traveling to an unknown place, hanging by the beach or at a cafe, or just finding yourself in a busy place, the Flack Sack II is ready for the challenge. This bag is the ultimate portable safe that allows you to live more and worry less.

LOCTOTE combination lock, steel reinforced straps and slash resistant ropes

The steel reinforced locking strap and heavy-duty solid brass lock enable you to lock your sack shut, and secure to a fixed object. It's slash-resistance is an effective deterrent for would-be thieves looking to to cut, break or tear through the bag.


Made from a single chunk of solid brass to ensure the security and durability of the lock. Easily set the lock to any combination you would like.


Made with a slash resistant core interwoven with a highly-reflective material for night visibility. Even though we hope no thief ever tries to cut this bag off your back, it’s nice to know they won’t be successful.


Protect against RFID electronic pick-pocketing. This sack has an internal pocket lined with a certified RFID blocking material to shield credit cards & passports from unauthorized scanning.


Gives you that extra security and comfort. By keeping the ropes centered across your chest, the bags stay secure with its weight comfortably distributed across your shoulders.


Our bags are lined with a water resistant nylon lining and is equipped with a large tablet-sized water-resistant interior pocket crafted with an Aquaguard zipper to keep your stuff as dry as possible.

LOCTOTE RFID blocking fabric, sternum strap, water resistant fabric

Flaknit Fabric


Our slash-resistant toughness comes from the superior cut protection of Honeywell's UHMWPE Spectra fiber, the same fiber used in police vests and military gear for bullet resistance. Feel the peace of mind from knowing your belongings are protected by this stuff.

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We told you it’s good...

Customer Reviews
4.8 Based on 623 Reviews
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Filter Reviews:
renato t.
Italy Italy

Amazing bag & perfect customer support

two years ago I bought two bags for me and my son - the Flak Sack is an incredibly sturdy, safe and the color is perfect. In November I bought two more bags, for my wife and my dear friend. The package was lost and customer service immediately sent another package with the fedex courier with a gift. Thank you

Ronaldo N.
Italy Italy

Beautiful backpack!! Modern and versatile!! It has a large capacity than I expected

Josefina O.
United States United States

Its use is very significant.

Thank you, we got it. This is our second purchase because the first one got borrowed but not returned. This is our travel buddy we badly needed. Mahalo