In professional video DJing and music curation contexts, typically refers to a video file formatted at 105 Beats Per Minute (BPM) in MP4 format. These files are highly valued by DJs for smooth transitions during sets.
Mentioning "105" specifically signals to other DJs that you are focused on technical precision and beat-matching. 105 mp4
If you are looking for the files themselves, they are often found in: In professional video DJing and music curation contexts,