The Thermal Conductivity of Graphite constant displays the value of the thermal conductivity for graphite (200 W/mK).
Thermal conductivity is defined as the measurement for the heat transfer characteristics of a solid material through conduction. The thermal conductivity of most liquids and solids varies with temperature. For vapors, it also depends on pressure. The thermal conductivity of graphite is 200 W/mK.
Material Properties (https://material-properties.org/graphite-density-strength-hardness-melting-point/)