For this game you need two laundry balls and an empty paper roll.
You need to wash the laundry balls properly before you give them to your dog.
The diameter of the rolls vary depending on the manufacturer. You can adjust the difficulty by changing the rolls thinner or wider so they are either easier or harder to pull out of the laundry balls.
Because Miki is advanced hunter-gatherer :D and has very high motivation I chose wide rolls so they are quite difficult to pull out. Therefore if your dog is a beginner you may want to choose thinner rolls so they are easy to pull out.
I put some kibble into each laundry ball and then I pushed the roll between them. I pushed them quite deep and because the rolls fit tight the kibble didn’t fall out even when Miki tore the roll in half.
I gave three of these dumbbells to Miki and it took under 10 minutes to get all the kibble out.