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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 138 reviews
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.

K. Hart
Booster Block

Fits perfectly in the sack. Have not had a chance to use the booster block due to inclement weather. I will use it soon!

just what she needed

The booster lifts my little tripod up enough so she can see the world from my point of view. Fits perfectly and seems comfortable for her. The carrier is perfect now for when she gets too tired to walk all the way back from wherever we’ve been.

Ann Vickers
Pup sits pretty

The block allows our girl to sit a little higher in the sack, which makes her look more comfortable.

Game changer

That block is definitely a game changer. I have a 10 pound chihuahua and the XS sack seemed too big until I placed the block.
The block is also well made..