24dBi Grid Antenna & 8dBi Yagi Antenna Grid Aetenna:1710-2170MHz The grid antenna is huge; The maximum receiving range of the antenna is about 1km. Yagi antenna: 824-960MHz Yagi The antenna is 8dBi, and the maximum receiving range is about 1km. 900 1800 2100 signal intensifier Gain: 70 dB Compatible with: LTE 1800; GSM 1800； 3G WCDMA 2100 24dBi grid antenna If the outdoor signal of the roof is weak, the grid antenna is the best choice for receiving 3g/4g from a long distance. Grid antenna is much better than omnidirectional antenna and log periodic antenna. So if your outdoor signal is less than 2 bar, don't waste money to buy cheap antennas. Only this grid antenna can solve your problem Question. Before you buy please check your frquency first.If you don't understand ,please cantact us.