Made in Switzerland, the Schertler DYN-M is unique among the acoustic pickups listed on this site, because it operates on electrodynamic rather than piezoelectric principles. The difference is ... the difference is ... well, perhaps you'd better visit the Schertler Web site and find out for yourself. It is one of the most expensive units you can get—but, considering the acclaim Schertlers have received, it just might be worth it. There's also a mandolin version of Schertler's new "Bluestick" saddle pickup that should be worth checking out.