Two. The 15km transmission length can only be obtained under the FCC standard when measured in an out of doors natural environment without having interference. The SRRC conventional is adopted in mainland China, along with the furthest transmission distance is eight km. Mavic 3M with RTK module for centimeter-level positioning. https://m3mhomes.com/m3m-india-offers-a-golden-investment-opportunity-in-gurgaon/