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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 142 reviews
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

Heather JH
Love our backpack & booster block!

Our pups love riding with us in their backpacks! I bought the booster because my skinny, floppy, poodle mutt was slouching down a bit low in the pack.

The right amount of boost!

This provides just the right amount of boost in a small sack for my 14 lb chihuahua!

Stacy W
Too cute

I bought the extra large sport pack for a growing puppy. I'm using the medium block inside along with a folded sheet, to boost my pup to the right height. The sport pack is too cute. It's well made and it's so easy to load my pup up. He seems content with the ride.