2.4GHz FHSS4 Spread spectrum system 4ch SSL support (ESC: Super Vortex Series etc.) Integrated Antenna Sanwa Super Response (SSR) help Specs: Frequency :2.4GHz FHSS4 Channel :4CH Nominal Input Voltage :3.7V~7.4V Proportions :18.2x24.4x27.1mm Weight :7.1g Suitable radio: M12, Exzes Z, MT-4S, MT-4(No SSL support)