What is required to get the strobes? Can the strobe effect be turned on and off?

 

i am not sure who makes them , whelen maybe. i put the bulbs in transparant blue paint(like vht). i hot glued them in place and put them on a batt+ switch so they could be on when i was parked. i lost most of the affect when i put a cap(topper) on my truck, but it still looks cool reflecting off the glass.