Nowadays such blockers, also known as jammers, are extremely popular and have many usages. The range of jammers is truly great that's why you can easily choose the necessary type of jammer to block any radio frequency you need. The most commonly used jammers are the ones that jam GSM, GPS and Wi-Fi bands. The legality of such type of blockers differs highly in various countries. In several countries it's even forbidden by law to use jammers of any type. Notwithstanding blockers are very popular among ordinary people. Especially jammers are highly in demand in large cities and megacities. In spite of the illegality, jammers are still popular because they are ideal for usage in many cases such as: 1. To disable cell phones in operas, cinemas and other places 2. To interrupt mobile phones in health care institutions 3. To shield conference spaces from industrial espionage 4. To fense offices from spying gizmos 5. To achieve absolute informational safety 6. To preclude people from spying on you and detecting your location 7. To preclude explosion of several kinds of bombs 8. To prevent cheating at different tests and exams 9. To prevent fakements of voting process during different elections 10. To fense militaries from homing missiles 11. To help police forces in struggling against the bandits Notwithstanding, few disadvantages of jammers can also be names. For instance, jammers: 1. Can and will be used during carjacking 2. Are used by bandits in many ways 3. Infringe the rights of communication corporations 4. Make impossible to call 911 If speaking about the advantages of using the blockers, the first thing that is mentioned is the ability to jam mobile phones in public places such as operas, movie theaters, restaurants and so on. Sometimes people can't or just don't want to understand that their blabbing on the mobile phone annoys people around them. This webresource has the best cell phone jammer available online.