This car speakerphone earned The Best rating from the Hammacher Schlemmer Institute because it provided the highest sound quality. Unlike lesser models that crackled at the highest setting or were inaudible in windy conditions, this unit streamed loud and clear audio without static or interference leading one analyst to say “I couldn't even tell they were talking on a speakerphone.” The Best Car Speakerphone mounts to a visor and once initially paired, automatically connects to your iPhone or Android via Bluetooth upon entering the vehicle. It allows one to make and answer phone calls using voice commands as well as stream phone calls, podcasts, music, and GPS directions (from a mobile device’s app) that are “as clear as listening to the radio.” A four-hour charge using the included USB charger or DC car charger provides 16 hours of talking time or 1,200 hours of standby time. 5" L x 3 1/2" W x 1 1/2" D. (6 oz.)