Based on the LG website specs, it looks like it only supports CDMA, no GSM
Network CDMA Dual Band, EVDO Rev 0/Rev A, eHRPD, LTE Dual Band*
Frequencies CDMA PCS 1.9 GHz, CDMA 800 MHz, LTE Bands 4/13*
Data Transmission EVDO, EVDO Rev A, 1xRTT, LTE*
All listed frequency support is network/carrier specific. Roaming capability and network frequency support may not be available. Check with your network provider to see if and to what extent they offer support for this device.