The Royal Sovereign RCD-1000 ultraviolet counterfeit detector provides a compact and portable counterfeit detection solution for businesses and organizations in the constant fight against fake bills and IDs. The UV rays easily detect fake bills and ID cards by revealing fluorescent strips, dots, and other markings that are invisible to the naked eye. The unit also comes with a UV detection guide for 20, 50, and 100 dollar bills that will show what markings to look for in authentic bills.