Using glass-mount exterior antenna for mobile wireless signal booster
Yes, you can use glass mount antenna for outside of your vehicle but that glass-mount tower antenna should be mounted as far as possible from the device antenna, preferably on the rear window of the vehicle. This is done to prevent oscillation.
Oscillation happens when the antennas pick up each other's signals and a feedback loop is created. The signal booster will detect oscillation and shuts down to prevent damage. A red indicator light will normally signal that oscillation has occurred. Consult the booster’s installation guide for more details.
With a roof antenna, the metal roof forms a shield between the two antennas, thereby preventing oscillation. With a glass mount antenna, signals pass through the glass and cause oscillation more easily.
On another note, what would you do if your vehicle has fiber glass roof or non-metallic roof that does not attract magnets? Get a sticky pad mounted external antenna vehicle cell booster.