NCAA Purdue Boilermakers 16oz Crystal Freezer Mug 16 ounce crystal freezer mug with team color handle and base Uses patented non-toxic refreezable crystal gel Place in freezer for 30 minutes to an hour Freezer gel keeps drinks cold without needing ice. No more diluted drinks! BPA free, lead free, safe to use Place in freezer one hour or more prior to use, when frozen crystals will turn a frosty white color 16-Ounce mug combines state of the art refreezability with team colors and graphics Filled with non toxic, refreezable crystals Eliminates the need for ice as the technology keeps drinks "crushed ice" cold for hours without the watered down affect of ice Not recommended for Dishwasher or Microwave