What's this component and its function?

It's so pesky searched for hours on what this component is without any helpful end

It's a mains filter choke.

Can't see a bigger picture but would guess it's not rated for much current.

Mike.

common mode choke filter
Data sheet for a part like that. They come with different amounts of turns of wire and thick ness of wire. If you look at the graphs in the data sheet this data sheet shows it was designed for 100kh to 300khz switching power supplies and works on the power line.
WE Here shows 10 different versions of that part. Each company makes them slightly different. Sorry they want to put cookies on your computer. So save you from the cookie monster here is a screen shot of what they have.