Forty-nine Washington, D.C. police cars have installed newfangled sirens that literally shake the ground and rattle passersby.
Meet the Rumbler. The high-tech blaster is being used along with the traditional siren. It is aimed at grabbing people's attention and getting them to make room for officers responding to emergencies, helping police navigate through traffic faster and safer. People can feel it from about 200 feet away.
Anything to calm down people who might be worried about cops blasting this as they drive past them on the street or speed through their neighborhoods?
"Once they see what it's attached to, they'll be all right," Assistant Police Chief Diane Groomes said. "They'll get used it."
More reasons to trust whatever the police do here.