For one, the "UWA" stands for ultra-wide angle, but a 58° AFOV doesn't translate into what it accepted as an ultra-wide TFOV. That would be at least an 82° AFOV, and greater.
Here's a BST 1.25" 4mm "UWA" 58°, and practically identical...
It's probably safe to say that it's an overseas knock-off.
Incidentally, I don't really consider BST to be a brand; more like a generic.
The one you have seems to have nice coatings, and perhaps even fully multi-coated like the BST.
Edited by Sky Muse, 08 November 2019 - 02:13 PM.