Does this work on fortinet 448e, 1024d, or 1048e?

Yes, it works with Fortinet 448e, 1024d and 1048e. Base on our experience, Fortinetare switch is whitebox device, does not require special EEPROM info, so if the device support 10G SFP+ Port, the 10Gbase-SR should have no issue working with them.