Because web searches for this exact string yield no direct matches, it is highly likely that this term is one of the following:
"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. 9684mp4
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 . Because web searches for this exact string yield
Could you please provide a bit about what this item is or where you saw the name? 9684mp4