Review on Bingfu 4G LTE TS9 Antenna - Powerful 7dBi Magnetic Base Cellular Antenna for Optimized Compatibility with Verizon, AT&T, T-Mobile, and Sprint. Ideal for 4G LTE Mobile Hotspots, MiFi Routers, Cellular Broadband Modems, USB Modems, and Dongle Adapters. by Rick Booth

First of all I would like to say that I only bought one. And connected it to the main connector. I have a Nighthawk M1 and for the first 6 months I didn't even know it had connectors for an external antenna. After finding the main port. After some internet searching for local antennas provided by phone companies near me and which was the closest and what frequencies it was producing. Found this antenna that was in a specific frequency range that I particularly liked because of the less traffic and better performance. First plugged in an antenna and it didn't really work because my internal antennas still want to reach the other tower which they thought was better. In the car it was said that the tower with internal antennas was better. But after the router blocks all signal, reset it and turn it back on. It connected to external antennas and left them on, didn't turn off after 2 minutes or an hour or anything. I bet if I tinker a bit and put the antenna in a really good spot on my roof I'll get a full signal. This is with only one antenna, I couldn't imagine what would happen if I had two!