This is an internal capture card for your PC (it uses one PCIe 3x4 slot) with built-in HDMI 2.1.
Can capture your PC or connect to console (Xbox, PlayStation, and Switch 2) with full 4K/144Hz pass through (and VRR for smoother gaming). Supports widescreen displays and HDR, too, and has customizable RGB lighting.
Normally goes for around $250-270 new, this one has never been used.