i need info about cell phones boosters for at&t 4 glte phones what MHz should i get

I'm assuming that you don't want a Mcell because it will not handle 4g/LTE bandwidth?

If so, there are boosters that will work on AT&T cell phones.  The Cel-Fi Pro is AT&T authorized and will cover the necessary frequencies to handle 3G, 4G and 4GLTE bandwidths.  They are not cheap ($700).  weBoost also makes a variety of boosters.  The Cel-Fi is self-contained and plug and play.  The weBoost boosters will require the installation of indoor and outdoor antennas.

Whatever booster you decide on, it needs to be able to handle 700 MHz, 850 MHz, 1700 MHz, 1900 MHz and 2100 MHz in order to cover all the AT&T frequencies.

The MicroCell is currently designed for 3G bandwidth only. If  you want/need 4G/LTE in home then you will need a signal booster (the MicroCell is technically not a signal booster). There are signal boosters available that will work on AT&T and other networks for 3G/4G/LTE but they can be pricey. See the Tech Guide (link in my sig) for more information. If you are asking about the actual frequencies that AT&T uses for 4G/LTE that info is in the Guide as well.

Beat you on this one!