A thermosetting powder coating composition comprising the following components A to C: A: one or more unsaturated resins comprising ethylenic unsaturations selected from the group consisting of polyester resins, acrylic resins, polyurethanes, epoxy resins, polyamides, polyesteramides, polycarbonates, polyureas and mixtures thereof, and B: one or more curing agents selected from the group consisting of vinyl urethanes, vinyl functionalized urethane resins and mixtures thereof, wherein at least one curing agent is curing agent A which is selected from the group consisting of i), ii) and iii): i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VU-c are in the region of from and including 30 up to and including 80 °C, and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VFUR-c are in the region of from and including 30 up to and including 80 °C, and iii) mixtures of crystalline VU-c and crystalline VFUR-c, wherein the ΔH m and T m is each measured via Differential Scanning Calorimetry according to the description, and C: one or more thermal radical initiators, wherein at least one thermal radical initiator is peroxydicarbonate-X which is present in an amount of at least 26 and at most 500 mmol/Kg A and B, and wherein the peroxydicarbonate-X is selected from the group consisting of peroxydicarbonates represented by the following formula X, and mixtures thereof, wherein R 1 is C 9 -C 22 saturated hydrocarbyl, and R 2 is C 9 -C 22 saturated hydrocarbyl. A: one or more unsaturated resins comprising ethylenic unsaturations selected from the group consisting of polyester resins, acrylic resins, polyurethanes, epoxy resins, polyamides, polyesteramides, polycarbonates, polyureas and mixtures thereof, and B: one or more curing agents selected from the group consisting of vinyl urethanes, vinyl functionalized urethane resins and mixtures thereof, wherein at least one curing agent is curing agent A which is selected from the group consisting of i), ii) and iii): i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VU-c are in the region of from and including 30 up to and including 80 °C, and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VFUR-c are in the region of from and including 30 up to and including 80 °C, and iii) mixtures of crystalline VU-c and crystalline VFUR-c, wherein the ΔH m and T m is each measured via Differential Scanning Calorimetry according to the description, and i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VU-c are in the region of from and including 30 up to and including 80 °C, and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH m ≥ 35 J/g, and one or more melting temperatures (T m) wherein any and all of the T m of the one or more crystalline VFUR-c are in the region of from and including 30 up to and including 80 °C, and iii) mixtures of crystalline VU-c and crystalline VFUR-c, C: one or more thermal radical initiators, wherein at least one thermal radical initiator is peroxydicarbonate-X which is present in an amount of at least 26 and at most 500 mmol/Kg A and B, and wherein the peroxydicarbonate-X is selected from the group consisting of peroxydicarbonates represented by the following formula X, and mixtures thereof, wherein R 1 is C 9 -C 22 saturated hydrocarbyl, and R 2 is C 9 -C 22 saturated hydrocarbyl.