KKmoon Portable RFID 125KHz Proximity Smart EM Card USB ID Reader Win8/Android/OTG Supported R60D USB Plug and Play. Widely used at apartment, office, supermarket etc. Support Working System: Compatible with in8/7/XP/Android System etc Working Range: about 0-8cm Reading Distance. Support Card Type : TK4100/EM4100/EM4001 Cards Muti-Fuction :that Soupporting OTG Smart Phone Connection.