What does this diode do?

[Barcode]

iMarkup_20201006_212513.jpg
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(Below is the downgrade of the product above.)

This is next to NTC and I have been told this is a relay substitute. (There is no relay on this PSU)

Some say it's TVS, but I know TVS as a substitute for MOV. So I don't think so.

What exactly is this and what does it do?

[ashiekh]

Just a guess:

Could it be a diode to protect the transistor from the coil's inductive kick? (some power transistors have a built in flyback diode).