The ECHO 2 PCB Antenna from Siretta provides you with a quad band, GSM, GPRS, 3G and 4G solution for your designs. . Features & Benefits of the ECHO 2 PCB Antenna. •GSM/GPRS 850, 900, 1.8, 1.9 MHz. •3G 1.9, 2.1 MHz. •4G 900, 1.8 MHz. •ISM 868, 2.4 MHz. •G