Dog Backpacks
K9 Sport Sack Knavigate — Internal Frame, 4 to 50 lb
K9 Sport Sack Knavigate — Internal Frame, 4 to 50 lb
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The serious one. An internal frame and a padded hip belt, which is the difference between carrying a dog and wearing one: the weight sits on your hips instead of hanging off your shoulders. The maker builds it for biking, hiking, skating and full days outdoors, and it is the only model here that goes to 50 lb.
The measurement that matters here
A carrier is sized by the bag. A backpack is sized by the dog. Measure along the spine, from the collar to the base of the tail, and buy that size — the weight limit is the second check, not the first. Between two sizes on length, go by weight: this rides on your shoulders and a bag that is too big swings.
- X-Small — 10–13 in from collar to tail
- Small — 13–17 in from collar to tail
- Medium — 17–20 in from collar to tail
- Large — 20–23 in from collar to tail
- X-Large — 23–26 in from collar to tail
Up to 50 lb in every size. No airline takes a dog backpack under the seat with the dog inside it, so none of the numbers on this page are cabin numbers.
What it does well
- Internal frame. The pack keeps its shape instead of collapsing around the dog when you lean forward.
- Padded hip belt that takes the load off your shoulders on a long climb.
- Storage under the base for treats, keys and a lead.
- Adventure-grade fabric and padding on the straps and back panel.
This listing is Lunar rock and Midnight black. The same pack in Dune is a separate listing.
This is a backpack for walking, not a carrier for flying. It is worn, so the space it needs is your back, not the space under a seat. If you are booking a flight, our cabin carriers publish a footprint and a height checked against nine U.S. airlines.
How to measure your pet
How to measure your pet
Two measurements decide everything.
Length. With your pet lying down, measure from the nose to the base of the tail — not the tip. Add 2 inches. That is the interior length you need.
Height. With your pet standing, measure from the floor to the top of the head.
Your pet must be able to stand up and turn around inside the carrier. That is the rule every airline writes, and the one gate agents actually check. If your pet falls between two interior sizes, take the bigger one — but check its exterior against your airline first. A bag your pet fits in but the airline will not take is no use to either of you.
Shipping & delivery
Shipping & delivery
We ship within the United States only, from warehouses in California and Nevada. Orders placed before 1pm ET on a business day are handed to the carrier the same day; after that, the next business day.
Delivery is typically 1–5 business days depending on how far you are from the warehouse. Shipping is free on every order, with no minimum — you never pay for delivery. Alaska, Hawaii and Puerto Rico are included at the same price; allow a few extra days for those three.
You get a tracking number by email as soon as the label is created.
Returns & exchanges
Returns & exchanges
Thirty days from delivery, in the original packaging and unused. Email us and we will send you a return authorisation and the address for that warehouse before you post anything — a parcel sent back without one cannot be credited.
Wrong size is the most common reason people write to us, and it is the easiest to solve: tell us your pet's measurements and your airline and we will tell you which size to swap to.
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The measurements come first
Sized before it is listed
Every carrier lists a length, width and height. Every backpack lists the back length and the weight limit it is built for. The numbers are on the page before you buy, not in the box after it arrives.
Shipped from inside the U.S.
California and Nevada. No customs form, no six-week wait. Most orders leave in a single parcel; where a kit is drawn from two different warehouses we say so on the product page.
Ask before you buy
Send us your pet’s measurements and your airline. We will tell you which size to order, or tell you honestly that we do not have one that fits.