Speak out,operates at the 850 mhz and 1900 mhz gsm band. Most of the established players, like rogers, bell and telus, also operate at that frequency. An amplifier will only work in an area in the building that can get some cell signal. I would recommend you buy one from a vendor that has a decent return policy. When the boosters work, they work great. But there are situations where it will not work, and it is hard to find that out until you actually test it out.