The invention relates to a smart junction box made from a thermally conductive thermoplastic polymer composition comprising a thermoplastic polymer, between 10 and 40 wt. % of a thermally conductive (TC) filler, between 15 and 30 wt. % of a flame retardant (FR) and between 20 and 45 wt. % of glass fibres (GF). The invention also relates to a polymer composition comprising between 25 and 67.5 wt. % of at least one aliphatic polyamide, between 10 and 40 wt. % of a thermally conductive (TC) filler, between 15 and 30 wt. % of a flame retardant (FR) and between 7.5 and 40 wt. % of glass fibres (GF), wherein the weight percentages (wt. %) are relative to the total weight of the composition.