Nowadays some of the best counterfeit banknotes are called Superdollars as a result of their good quality, and likeness to the real US dollar. The resources of these supernotes are disputed, with North Korea being vocally accused by US authorities. There's the AccuBANKER Cash + Card Counterfeit Detector, at this https://bookmarkyourpage.com/story2290716/everything-about-real-counterfeit-money-for-sale