You can open it using Windows Media Player or QuickTime by double-clicking it.
It is supported by almost every digital device and media player. 454454 mp4
While the file is technically a square 454x454 MP4, the device "crops" or masks it to fit the circular glass. 🎥 Why Use MP4 for This? You can open it using Windows Media Player
It can hold essential data like subtitles and chapter info, which is useful for guided workout videos on watches. How to Handle These Files Opening and Playing If you find a 454454 MP4 file on your computer: a short notification clip
Likely a watch face animation, a short notification clip, or a wearable app asset.