Review on 🤲 Isoflex Stress Relief and Hand Exercise Marblized Assorted Colors - 1 Pack by Tony Chandler

I love this stress ball, but know that you should treat it as a "throw away" item. I completely destroy one every 2-3 months, so they are by no means "permanent" or long-lived. As others have said, there is definitely a "breaking-in period". Softening lasts several days. I would say that after a month or two the outer layer wears out, then the last, inner layer cracks and scatters finely ground sand. It's usually a gentle crack so it doesn't explode or anything.