YKS Upgraded Arduino APM 2.8 Flight Controller Board built-in Compass w/ Shock Absorber for RC Quadcopter APM2.8 Flight Controller, APM2.5 2.6 Upgraded version,newest APM version. Includes 3-axis gyro, accelerometer and magnetometer, along with a high-performance barometer. Barometric pressure sensor upgraded to MS5611-01BA03, from Measurement Specialties. Onboard 4 MegaByte Dataflash chip for automatic datalogging.Optional off-board GPS, uBlox LEA-6H module with Compass. One of the first open source autopilot systems to use Invensense's 6 DoF Accelerometer/Gyro MPU-6000. Atmel's ATMEGA2560 and ATMEGA32U-2 chips for processing and usb functions respectively.