Identifying "plastic" square loop toroid

[neazoi]

I have taken two square loop toroids out of two PC SMPSUs which have a plastic body and insise (they can open) tape wound with some kind of metal material.
The code on them is FS-1505 and the plastic is black.
Has anyone come across these and can identify the model or even the company that produces them?

 

[KlausST]

Hi,

What about a photo?

Klaus

 

[neazoi]

Hi,

What about a photo?

Klaus

It is like this http://qrp.gr/squareloop/cores.png the top left open core

 

[FvM]

Tape wound core

--- Updated Jan 30, 2022 ---

Different vendors and materials. See portfolio of VAC amorphous and nanocrystalline cores https://www.sekels.de/fileadmin/PDF/Englisch/21_Tables_of_VP_and_VC_standard_core_series.pdf