Dark grey vulcan stone large the perfect stone to remove calluses and hard skin from feet and hands. ergonomic and round shapes. these vulcan pumice stones have been designed according to nature’s colors and forms. their rounded but imperfect lines confere them a touch of elegance. eco-friendly totally eco-friendly. it does not contain plastics or polluting agents. chemical free without toxic chemicals or petroleum-based components. free of toxic substances. maximum quality carefully made in spain. every unit passes through several quality controls. effective the most effective in the world. it effectively removes hard skin and calluses. hypoallergenic tested by independent laboratories and certified to be safe for skin. bacteriostatic its structure does not allow bacteria to grow on it.