These last a long time and Rosie will chew it for hours. I can rarely find something she'll keep herself occupied with and this always does the trick. The only problem is the plastic sometimes gets sharp cuz Rosie chews both the center and plastic part. She loves them too much though for me to not give them to her
She hasn't gotten sick from them and it lasts us almost 1 week.
You should also try the everlasting treatball