Dr. Scholl’s CALLUS Removers with Duragel technology removes calluses fast in as few as two treatments! The Duragel technology provides all day cushioning pain relief and helps soften hard calluses. This product provides maximum strength salicylic acid without a prescription. Dr. Scholl's Callus Removers are thin and flexible and stay on all day and night. The package contains 4 medicated discs and 4 cushions. Dr. Scholl's has been a trusted brand in foot care since 1904 when Dr. William Mathias Scholl, grandson of a cobbler, launched the company under the name Dr. Scholl Inc.