Two. The 15km transmission distance can only be realized under the FCC common when calculated in an outdoor ecosystem without the need of interference. The SRRC typical is adopted in mainland China, plus the furthest transmission length is 8 km. Mavic 3M with RTK module for centimeter-degree positioning. Flight control, https://m3mhomes.com/residential/m3m-industrial-plots-sector-9-manesar/