Use gently on intact skin as part of your hand-care routine between climbing sessions.

The Gift Every Climber’s Hands Need 🎁
A Simple Hand-Care Ritual for Climbers
What Climbers Love About ClimBall
Simple, well-made and effective for building grip and hand toughness. The large size is comfortable and the texture is a good challenge. 4 stars only because results take consistent use, but it works as advertised.
Bought it as a rock nerd, not for calluses. It's very rough, hard and light, so it should work for skin conditioning. Downsides: it leaves black dust on your hands, and mine looks plainer than the listing photo. Still neat on my shelf.
Perfectly round and great for smoothing calluses on hands and feet, especially after a hot tub soak. About tennis-ball size, surprisingly light and durable, with a texture you have to feel to understand. A long-lasting callus ball that really delivers!
A Climbing Challenge for Every Day
Turn any desk break into a finger-climbing challenge. Follow the included route cards, test your skills, or rearrange the holds to create your own routes.