The RFID Reader 125KHz by Fissaid is a USB reader emulator designed to read proximity cards and EM4100 ID cards. With a data transfer rate of 40.0, it is compatible with personal computers and features a sleek black design. The reader weighs 0.24 pounds and has dimensions of 5.39x3.66x1.26 inches. It is suitable for various operating systems including Linux, Windows, Android, and Mac OS, making it a versatile and efficient tool for surveillance and alarm systems in a business or industrial setting.