Material - High Quality 35 Mil Magnetic Material -- Size - 3 3/4 Inches (L) -- Care Instructions: Remove Weekly for Surface Cleaning and/or to Change Placement -- Magnets are Made in the USA -- These are Perfect for Both Indoor and Outdoor Use. These are Perfect for Placing on Garage Doors, School White Boards or Lockers, Dishwashers, Refrigerators, or Any Other Magnetic Surface