Bnk extension is associated with Bink video and audio files. You can try to open these with Bink Video software.

Bink firm generally produces advanced video file system for the purpose of using with games. The bik extension file which is developed by the same firm is more popular.  Bink system produces better quality and small sized files as against other video formats. 

You can learn more information about the program from following links.

What to use bnk

Bink Video

which page related to bnk file

bnk Related Searches

You can check related links about bnk fileextension.