PE - protective earth (or ground) in mains socket.
CCA - copper clad aluminum i.e. aluminum strands coated in copper. It may look like copper, but it is a bad choice as cable conductor for many reasons.
Also, run with a strong magnet over the wires. Wires should not be magnetic, but who nows what you will find at this quality level.
Double fuse idea is for potential line/neutral reversal or unusual situations, just in case.