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K9 Booster Block


Sizing your dog for a K9 Sport Sack® isn't an exact science. If your dog is in between sizes, has a wide body but short in length, or is still growing, the Booster Block fits snuggly in the bottom of your K9 Sport Sack to boost your dog up 3" (7.62 cm). It helps make the K9 Sport Sack experience more comfortable for you and your dog.

  • Constructed of sturdy, quality foam
  • Removable, washable cloth cover
  • Use two blocks for a 6" lift
  • XS/S measures 3" tall * 8" wide * 5" deep (7.62 cm * 20.32 cm * 12.7 cm)
  • XS/S are interchangeable between XS and S sized backpacks
  • M/L measures 3" tall * 10" wide * 6" deep (7.62 cm * 25.4 cm * 15.24 cm)
  • M/L are interchangeable between M and L sized backpacks and are also compatible with XL and XXL if necessary

Customer Reviews

Based on 145 reviews
Great purchase!

Forgot to get a picture on the trail, but so glad I got the booster! It just helps Jaxx sit a little higher on my back so his weight is better distributed for me. He's 13lbs but long legs, so he's in a medium sportsack with booster.

Lori R

I was really nervous on what size to order for my little guy. I called K9 and Customer Service talked me through it, so kind and helpful! As you can see my sweet boy loves it! 🐾💜

Amy Agredano
Lift it up

My dog was in between bag sizes, so we went with the larger size. He was a bit too low in the bag which wasn't just uncomfortable for him, but it caused the weight of him to hit midback which was uncomfortable for me as well. The booster block is perfect as it gives him just enough lift that he and I are both happier!!!

booty booster

This was perfect for our smaller dog. We have two dogs that fit the same sport sack but one needs a little boost. This was great for her.


K9 Booster Block