Usmile Beitian NEO-M8N GPS Module with Built-in HMC5883L Compass Protective Case for Ublox PX4 PIX APM2.5/2.6 Pixhawk Quick satellite searching,No more sitting and waiting for GPS locked, Few second and your quad good to go Compatible with the u-center Ublox software Built-in HMC5883L compass, Easy to setup, very fast lock, good quality for the money A great update for CX-20 or Walkera QR X350 PRO or other mid-sized quad, lock much more satellites and much more stable Small size and high performance. Be sure to check the wiring pinouts before hooking this up and disabling the onboard compass on your flight controller if you have one. LED Flashes blue means it functions normally, Flashes red means successful lock, no led means not working.