Not even , very common , electric wires embedded in the plaster ,

to the op, if the heat still works , then no problems ,
they are simply bare nichrome wires embedded in the plaster ,
carefully clean the cracks , and repair with plaster . or mud ,
being certain to not nick or scrape the wires . and then allowing
plaster or mud to set completely before powering them up .


good luck


Robert Barr wrote:
troll