Those are .rar files. You need an unrar utility to reassemble the individual components into a video.
The rar process compresses a video file and breaks it down into "bite sized" pieces that are suitable for emailing or other file transfer methods, and the unrar process decompresses and assembles the pieces back into the original video. Sometimes a password can be used to restrict who is allowed to reassemble the pieces.
here is a link to a free unrar utility
http://download.cnet.com/RarZilla-Fr...-10647724.html