Medium Expandable Backpack

Shop Now

Best around town expandable backpack for those with a small/medium frame.

Large Expandable Backpack

Shop Now

Best expandable backpack for those with a larger body frame who regularly need room to carry a lot of stuff.

Small Expandable Backpack

Coming soon

Join Wait List

One bag. Any purpose.

We design simple, intelligent bags that maximize space and flexibility so you can pack more into your life every day.

We want your bag to work for you. That’s why we created our Knack Packs in a few sizes. While each size bag shares many of the same great features, there are a few differences between them which we outline below.

Packing Dimensions
Medium Large
Medium Knack Backpack Unexpanded 17 Liters
17 Liters
Large Knack Backpack Unexpanded 22 Liters
22 Liters
Medium Knack Backpack Expanded 31 Liters
17 L + 14 L = 31 Liters
Large Knack Backpack Expanded 37 Liters
22 L + 15 L = 37 Liters
Additional Specs
Medium Large
Weight Icon
2 lb 11 oz 3 lb 4 oz
Laptop Icon
15" 17"
Plane Overhead Icon
All Jets All Jets
Plane Under Seat Icon
Under Seat
All Jets Doesn't fit (when expanded)
Outfits Icon
2-3 3-4
Water Bottle Pocket Icon
Water Bottle Pocket
17 oz S'well™ 25 oz S'well™
Tuck-Away Hip Strap Icon
Tuck-Away Hip Strap
No Yes

Size Chart

Model: 5'5"

Knack Backpacks on 5 foot 5 inch model



Model: 5'11"

Knack Backpacks on 5 foot 11 inch model



Model: 6'3"

Knack Backpacks on 6 foot 3 inch model



Backpacks Built for One Bag Living

Custom-Engineered Straps

When the usual methods failed, we custom-engineered the manufacturing process to attach our top handle and back straps to the backpack. We then filled the bag with over 30 pounds and jerked it up and down more than 3,500 times before we were confident it wouldn’t let you down.

Exhaustively-Tested Zippers

Not only did we test our YKK™ zippers and custom zipper pulls for strength, we also opened and closed them 5,000 times to make sure they would last.

Durable Buckles and Hardware

We crafted our bags using only durable, easy-to-use Duraflex™ Hardware.

Above and Beyond Details

We sweat the little things. Most bags are constructed using 5-6 stitches per inch in the seams. We use 7 stitches per inch. It costs a bit more, but we think the added strength is worth it.