**********Best Quality Guranteed. *****S500 is the quadcopter frame for upgrade F450 FPV Frame Kit. *****High quality PCB version carbon fiber material and exquisite design. *****PCB Center plate with solder point, good qiality carbon fiber landing gear; *****Good work with Gopro Hero 3 2 Axis brushless gimbal for FPV*****Learned arm design from DJI S800 EVO, and enhanced. *****