PETZL Power Ball Chalk GET A GRIP: The POWER BALL chalk ball improves your grip on rock or gym holds. DUST-FREE: The ball eliminates airborne chalk dust, making it ideal for use at the gym. EXTRA-FINE: The extra-fine mesh allows for an even application of chalk. NO CHUNKS: The POWER BALL is filled with fine chalk that ensures a steady, even coating to your hands. MATERIAL: The chalk consists of 100% magnesium carbonate and the bag is made of polyester mesh.