We always recommend always knowing the type of equipment you want to buy. It is best to read additional information and understand how these devices work. It's not that difficult, and rocket scientists don't need to know how signal jammer work. If we explain the whole process in a few lines, it will look like this: Your phone is a duplex device and it will use two types of frequencies: one is the frequency of speaking and the other is the frequency of listening. Basically causing your phone to be locked is to start transmitting the same frequency and lock the signal this way.
