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K9 Sport Sack Kolossus Big Dog Carrier Backpack

Man carrying a bulldog on his back in the K9 Sport Sack Kolossus dog carrier backpack
K9 Sport Sack Kolossus dog carrier backpack in black and grey, front three-quarter view
K9 Sport Sack Kolossus dog carrier backpack, side view
K9 Sport Sack Kolossus dog carrier backpack, side view of the padded shoulder straps and hip belt
K9 Sport Sack Kolossus dog carrier backpack, back view of the harness, shoulder straps and hip belt
Kolossus features: aluminum frame, padded hip belt, pockets, 60 L hiking pack mode
Why owners love the Kolossus dog carrier backpack
Kolossus size guide: Large 20-23 in, X-Large 23-26 in back length

Dog Crates, Pens & Carriers , Dog Backpacks & Bags , Dogs

K9 Sport Sack Kolossus Big Dog Carrier Backpack

Bring your big dog on every trail. Big dogs get tired, older dogs slow down, and some trails are simply longer than their legs. The K9 Sport Sack Kolossus is a dog carrier backpack built for larger dogs, so you keep going together instead of turning back early. When your dog wants to walk, it turns into a 60 L hiking pack.

  • GO FURTHER TOGETHER: This big dog carrier backpack lets your dog ride on your back when their legs give out, so long hikes, city days and travel stay a shared plan instead of a reason to leave them home.

  • BUILT TO CARRY WEIGHT: An internal aluminum frame, padded back panel and padded hip belt spread the load across your body. Dog owners at other stores mention how well built and comfortable it is.

  • FITS YOUR BODY TOO: Shoulder and torso sizing adjust to the person carrying. Two side pockets hold water bottles, a base pocket holds gear, and a waste-bag dispenser sits in the hip belt.

  • TWO PACKS IN ONE: Carry your dog on the climb, then switch it to a 60 L hiking pack with a removable storage bag and gear loops underneath. Sized by back length: Large 20–23 in, X-Large 23–26 in.

  • WHAT YOU GET: One K9 Sport Sack Kolossus in black, in the size you choose. Ships from US warehouses in 1–5 business days, with free shipping and 30-day returns if it isn't the right fit.

Care & safety

Measure your dog from collar to base of tail and around the chest before you choose. Start with short sessions at home, only carry a weight you can manage comfortably, and never leave a dog unattended in the pack.

Frequently asked questions

Which size should I choose?

Measure your dog from collar to base of tail. Choose Large for 20–23 in or X-Large for 23–26 in. Owners say the base runs narrow, so check chest girth too and size up if your dog is between sizes.

Which dogs is it for?

It is built for big dogs from 20 to 80 lb. Only carry a weight you can manage comfortably.

Can I use it without my dog in it?

Yes. It converts to a 60 L hiking pack with a removable storage bag, two bottle pockets and gear loops.

How do I get my dog used to it?

Start at home with treats and a few minutes at a time, then short walks, before a long hike.

How fast will it arrive?

It ships from US warehouses, and delivery takes 1–5 business days. Shipping is free on this item.

From $264.99
Size
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★★★★★3.9· 193 ratings elsewhere
Why we like it
  • Well built, with a frame and hip belt made for bigger dogs
  • Doubles as a 60 L hiking pack
  • Tip: it runs small and the base is narrow, so measure first
How to measure: with a soft tape, measure along your dog's back from the base of the collar to the base of the tail. Size by back length: • Large: 20–23 in • X-Large: 23–26 in Built for dogs from 20 to 80 lb. Only carry a weight you can manage comfortably. Between two sizes or not sure? Send us a message at support@fuzzyfiesta.com with your dog's weight and measurements, and we'll help you pick.
Most orders arrive within 1 to 5 business days of being placed, including the time we need to pack them. US shipping is free on orders over $69, otherwise a flat $9.95. You have 30 days from delivery to start a return — email support@fuzzyfiesta.com and we will confirm it and send you the instructions. If an item arrives damaged, faulty or wrong we cover it completely: a full refund including shipping, or a replacement, with nothing to post back. If you change your mind, return postage is yours. For hygiene reasons we cannot take back opened food, treats or supplements.

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Ships from US warehouses · 1–5 business days
Free US shipping over $69
30-day returns
Secure checkout
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