Could you please provide a bit about what this item is or where you saw the name?
If you are looking for tech reviews, you might be thinking of products like the TeamGroup MP44 NVMe SSD Go to product viewer dialog for this item. or the legendary 1988 McLaren MP4/4 Formula 1 car . 9684mp4
"9684" is sometimes used to denote large commercial dimensions (like a 96" x 84" sliding door), but this does not correlate with an "mp4" extension. Could you please provide a bit about what