This is GY-87 MPU-9265 3-axis 9-DOF Attitude Gyro Magnetometer Accelerator Sensor Module. GY-87 MPU-9250 9 axis attitude gyro is a 9 degree of freedom (DOF) device which incorporates an MPU6500 accelerometer and gyro chip, and HMC5883L digital compass.
There are different types of magnetometer are available; the basic differences between MPU6000, MPU6050 and MPU6500 is:
The HMC5883 is a surface mount multi-chip module designed for low field magnetic sensing with a digital interface for applications such as low cost compassing and magnetometry. The HMC5883 includes our state of the art, high-resolution HMC118X series magneto-resistive sensors plus Honeywell developed ASIC containing amplification, automatic degaussing strap drivers, offset cancellation, 12-bit ADC that enables 1° to 2°compass heading accuracy. Applications for the HMC5883 include Mobile Phones, Netbooks, Consumer Electronics, Auto Navigation Systems, and Personal Navigation Devices.