Why do heating coils of a room heater have a shiny curved metal surface?

The shiny curved metal surface of heating coils in a room heater is designed to enhance heat radiation and convection. This reflective surface helps to efficiently distribute heat throughout the room by directing warmth away from the coils. Additionally, the curvature increases the surface area, allowing for better heat transfer and improving the overall efficiency of the heater. The shiny finish also helps to minimize heat loss by reflecting radiant heat back into the room.