FortiManager sysVersion/Firmware version OID?

I am having a tough time getting the firmware version of my FortiManager 1000D, I have tried 

1.3.6.1.4.1.12356.101.4.1.1

1.3.6.1.2.1.25.6.3.1.2

Is there another OID or MIB I should be looking at? Thanks