I bought a 640 thermal camera but received a mislabeled 256 variant

I bought a 640x512 thermal camera but received a 256x192 variant with a fraudulent sticker claiming it to be a 640 variant. I was scammed.

The only easily distinguishable thing between the three variants is a sticker placed on the product, that's why I wanted to determine exactly which variant I received.

In this video I show how I found this out by measuring the FOV (field of view) of the camera I received.

The 640 variant should have a 48.3° Horizontal FOV, and I measured the camera I received to have a Horizontal FOV between 18-19°, which is within the 256 variant's claimed 18.1° Horizontal FOV.

The 640 variant should also have a 38.6° Vertical FOV, and I measured the camera I received to have 13-14°, also within the 256 variant's claimed 13.6° Vertical FOV.