A finned body comprising a power LED chip for a lighting apparatus comprising: - an element made of a heat-conductive material, said element having a front portion with a front seat for a power LED chip and a rear finned portion, wherein said rear finned portion comprises: - starting at a measured distance D from said front seat, a first plane slit that ends at a root that has a circular cross section of determined diameter Φ, creating between said first slit and said front seat a support base that has a thickness D; - starting at a measured distance D1 longer than D from said front seat, a second plane slit that ends at a root of said material that has a cross section of determined diameter Φ1, creating a first fin A1 between said first slit and said second slit; - starting at a measured distance D2 longer than D1 from said front seat, a third plane slit that ends at a root of said material that has a cross section of determined diameter Φ2, creating a second fin A2 between said second and said third slit; - further plane slits Fi that form said rear finned portion with said first slit, said second slit and said third slit, creating a respective fin Ai between two consecutive slits, up to a last fin An, each fin Ai of said rear finned portion at a distance d i from a previous fin, and each fin extending from a circular root of said material that has a cross section of diameter Φi, wherein first through holes are made on said front seat, said through holes crossing said finned body starting from said front seat towards said last fin An, said first holes arranged to receive electrical supply wires for said power LED chip; said finned body characterized in that second through holes are made on said front seat, in that said second through holes cross said finned body starting from said front seat towards said last fin and in that said second through holes are arranged to allow an axial air circulation and to assist heat exchange. - an element made of a heat-conductive material, said element having a front portion with a front seat for a power LED chip and a rear finned portion, wherein said rear finned portion comprises: - starting at a measured distance D from said front seat, a first plane slit that ends at a root that has a circular cross section of determined diameter Φ, creating between said first slit and said front seat a support base that has a thickness D; - starting at a measured distance D1 longer than D from said front seat, a second plane slit that ends at a root of said material that has a cross section of determined diameter Φ1, creating a first fin A1 between said first slit and said second slit; - starting at a measured distance D2 longer than D1 from said front seat, a third plane slit that ends at a root of said material that has a cross section of determined diameter Φ2, creating a second fin A2 between said second and said third slit; - further plane slits Fi that form said rear finned portion with said first slit, said second slit and said third slit, creating a respective fin Ai between two consecutive slits, up to a last fin An, each fin Ai of said rear finned portion at a distance d i from a previous fin, and each fin extending from a circular root of said material that has a cross section of diameter Φi, wherein first through holes are made on said front seat, said through holes crossing said finned body starting from said front seat towards said last fin An, said first holes arranged to receive electrical supply wires for said power LED chip; said finned body characterized in that second through holes are made on said front seat, in that said second through holes cross said finned body starting from said front seat towards said last fin and in that said second through holes are arranged to allow an axial air circulation and to assist heat exchange. - starting at a measured distance D from said front seat, a first plane slit that ends at a root that has a circular cross section of determined diameter Φ, creating between said first slit and said front seat a support base that has a thickness D; - starting at a measured distance D1 longer than D from said front seat, a second plane slit that ends at a root of said material that has a cross section of determined diameter Φ1, creating a first fin A1 between said first slit and said second slit; - starting at a measured distance D2 longer than D1 from said front seat, a third plane slit that ends at a root of said material that has a cross section of determined diameter Φ2, creating a second fin A2 between said second and said third slit; - further plane slits Fi that form said rear finned portion with said first slit, said second slit and said third slit, creating a respective fin Ai between two consecutive slits, up to a last fin An, each fin Ai of said rear finned portion at a distance d i from a previous fin, and each fin extending from a circular root of said material that has a cross section of diameter Φi,