Overview: The Wilson 811200 is a dual band amplifier that is designed to attach directly to your phone, by using a Wilson cell phone adapter. By attaching the amplifier directly to your phone's antenna port, you can greatly increase the signal improvement. The amplifier is dual band, and works will all US networks except Nextel. It will boost both voice and 3G data. The kit needs an external antenna to work. Alternatively you can buy a pre-packaged kit. Recommendations: Outside antenna: There are many options for the exterior antenna for this kit. For a full list of mobile antennas see this page. Adapter cable: To attach this kit you your phone you will need an adapter cable. We have adapter cables for most phone models - to check which one you need see our adapter cables category and check your phone/data card manufacturer. If your manufacturer is not listed, then you can try the Wilson SignalBoost kits, which have a universal adapter. Kit contents: 811201 Dual Band Direct Connect Amplifier 12V DC power adapter (car charger) Instruction manual