The R4, by Uniden, is an all new platform with a much greater range. It has a new Auto Mute Memory feature, which automatically locks out false alert locations. The R4 also has the best K Band filter on the market, offering the least amount of false alerts from blind spot monitors and K Band sensors in other vehicles. When you need the best information possible, and none of the noise, Uniden’s R4 Extreme puts you miles ahead.