This is a gsm wifi portable phone jammer,it is very popular online for sale of jammer-buy store.An official report reveals that car thieves have developed a new strategy to avoid arrest after stealing cars that might be equipped with tracking devices. Criminals are increasingly using this new method, called “kneading park” – they think they stole a car, and then place it in a safe place for days, in case the police get GPS jammer data from vehicle safety equipment. If the car is not taken away by the authorities within days of being taken away by the owner, the thieves know that it is safe to arrange for a new license plate to be installed and then sold or exported. https://www.jammer-buy.com/gps-jammer/c-25.html