The outer cover/sheath on the wire to my rooftop solar panel is cracked and broken off in several places exposing the two colored wires inside.  Is there a product out there that can be used to recover and protect?  I was thinking of something along the lines like pipe insulation -- a tube with a slit along the length that could be slipped over the wires, but it would have to be much, much smaller in diameter.

Any suggestions?