Hungarian Ulazslo I ?

It loks like Ulaszlo I…3 shields coin but have only 0.39g and looks like copper, 16mm.

Any opinion?

It does look like an Ulaszlo I denier: N#51206. The size and weight looks ok, considering how worn your specimen is.
About the copper: During  the reign of  Ulaszlo I the silver content of his coins diminished considerably. I found a remark in a book that his silver coins sometimes contains only trace amounts of silver, although they are nominaly silver coins. Plus the quality of the engraving also dropped, so it sometimes hard to disinguish if a given coin is a poor quality official issue or a contemporary fake.
(I found the remark on page 47 of this book: https://moly.hu/konyvek/pallos-lajos-torbagyi-melinda-toth-csaba-a-magyar-penz-tortenete)

Mine also has quite a copper-like color:  

© Sebastian Sann