firebacks

/ˈfaɪərbæks/
noun
  1. Plates of iron or other material placed at the back of a fireplace to protect the wall and reflect heat.
    • The fireback glowed red from the heat of the roaring fire.
    • We installed a fireback to improve the efficiency of our old fireplace.
    • The antique shop sold a cast-iron fireback decorated with a hunting scene.