Can I delete z-wave backup?

[Shazard]

Hi, this is what I see

pi@raspberrypi /opt $ du -sh *
37M vc
49M z-way-server
48M z-way-server_2014-09-18-19-48-28

is it safe to delete z-way-server_2014-09-18-19-48-28 with all it's content if I consider current z-way-server running fine and smooth?
48M is nice space to save.

[pz1]

I have done that several times without a problem