The RockRoller brings 2 elements to the scotch or whiskey experience; chilling & motion Traditionally scent, temperature and taste were the key elements for the enjoyment of scotch or whiskey, now the Rock Roller has added chilling & motion to the mix Dual rolling chilling balls provide zero dilution, and ensures your beverage a consistent flavour & aroma A simple wrist motion gently rolls each of the chilling balls around the bottom of the glass The curve in the lower bulb prevents the chilling balls from rolling out while sipping