thanks for all your feed back

@cyberphox Great then there should be no problem using it on a Pi 4.
What obstacles and restrictions have you experienced?
Can it use multiple touches or just single touches?

@Sean The frame will sit on top of the mirror which will be a 30/70 dielectric mirror is not a spyglass.
I’m pretty sure that part will work, where my concerns are is software.
Is it possible to control the mirror and make inputs with this product?

Does anyone have experience using USB IR touch screen frames on a Pi 4?
I’ve attached the one I’m looking at as a link.
http://keetouch.eu/en/touchscreen/wkmi-0400