... and 3g signal at the same time, but when you just want want to block the cell phone's signal ... , but not bloking the wifi and 3g signal, you can use the swith on the item's side ... 's signal. What functions you need, what functions you don't need, now you can use the swith to make what you need.Powerful and ... BACK FOR MORE, THIS JAMMER IS REALLY COOL, HOPE OTHERS ARE GOOD AS WELL. SEE YOU, GUYS.5. it\'s a ...