Royal Sovereign RCD-UVP2 Portable Ultraviolet Counterfeit Detector, 2 Units per Pack: * Easily detects fake bills and ID"s * Ultraviolet light easily detects security thread * Protect yourself from financial loss due to counterfeiting * Includes bill detection guide * Handy "How to Use" chart helps you easily locate the security threads you should look for on US currency * Also use to authenticate passports, credit cards, ID"s and more