there is no problem for T-Mobile and AT&T sim card, But no 4G!!!

There is no problem for T-Mobile and AT&T sim card, But no 4G!!! doesn't work for 4G card

Support Network

Quad-band SIM1/SIM2/GSM/GPRS/EDGE,  unlocked 2G:GSM 900M/1800M 3G:WCDMA 850/2100MHz