Not all media players are created equal. Because 300MB MKVs often use non-standard bitrates (variable bitrate, or VBR) and modern codecs, you need robust players.
Maybe you have a large MKV or MP4 file and want to shrink it to 300MB for your phone. Here is the ethical, legal method (assuming you own the media). mkv 300mb
The 300MB release is a study in compromise. The "WAF" (Wife Acceptance Factor) or general user enjoyment is often tested by: Not all media players are created equal
If you are building a site or blog that lists these files, you need a concise, keyword-rich summary: "Download the latest movies and web series in high-quality or VBR) and modern codecs