The Flysky FS-i4 is a affordable, 4CH 2.4G radio system and also a very simple setup for your RC vehicle. The automatic frequency hopping digital system provides a b, reliable 2.4GHz signal, so rest assured you'll always be in control. Included in the package is a 6-channel mini receiver that will fit in most vehicles. The ergonomic feel of the trasnsmitter will feel good in your hands even after long track sessions. Transmitter Specfications: Channels: 4 Model type: fixed-wing/glider/helicopter RF range: 2.405-2.475GHz Bandwidth: 500KHz Band: 142 RF power: less than 20dBm 2.4G system: AFHDS 2A and AFHDS Code type: GFSK Sensitivity: 1024 Low voltage warning: less than 4.2V DSC port: PS2; output: PPM Charger port: no ANT length: 26mm * 2(dual antenna) Power: 6V 1.5AA * 4 Display mode: LED indicator Size:174 * 89 * 190mm Weight: 335g Color: black Receiver Specifications: Channels: 6 Channels Model type: Airplane / Glider / Helicopter RF range: 2.405-2.475GHz Bandwidth: 500KHz Band sum: 142 RF Receiver Sensitivity: -105dBm 2.4G system: AFHDS 2A Code type: GFSK Sensitivity: 1024 Power: 4.5~6.5V DC ANT length: 26mm Dimensions: 45 * 23 * 9mm Weight: 13g Color: gray(transparent) Package information: Package size: 23 * 21 * 10.5cm / 9.1 * 8.3 * 4.1in Package weight: 564g / 1.3lb Gift box Package list: 1 * FS-i4 transmitter 1 * FS-A6 6CH Receiver 1 * Bind plug