... 0.7m- 0.9m (related with magnetic strips) EM System Library security Product Name Book Pickproof InstrumentProduct Model XLD-EM-02 ... Extremely low application cost6 Very good invisibility Wide ApplicationsBookstore Supermarket, Library, A&V Store, Drugstore Supermarket, Cosmetics Supermarket, and Various Open ... Main materials Resin8 Main-body color White and silver gray, Library security EM Antenna