Speaker binding posts with plastic covers

They aren't for personnel safety and not required by any code, they are to protect your amp from accidental shorting which is the most common cause of amp failure.  (Everyone says "it just failed!!!").

Usually you can unscrew them with your fingers and put a spade in. 

Jerry

Most people won't agree, but I would probably just replace the binding posts.  I make my own binding posts but they are low mass and very similar to these from KLEI.