A heat sink structure comprising: at least first, second and third heat sink regions (11, 12,13); at least a first circuit board; and at least first and second solid state light emitters, the first heat sink region having a first major surface that extends in a first plane of symmetry, the second heat sink region having a second major surface that extends in a second plane of symmetry, the first plane of symmetry defining an angle of at least 20 degrees relative to the second plane of symmetry, the first circuit board comprising at least a first circuit board region and a second circuit board region, and a third circuit board region, the first circuit board region on the first heat sink region, the second circuit board region on the second heat sink region, the third circuit board region on the third heat sink region, the first circuit board region integral with the second circuit board region, at least a first fold region between the first heat sink region and the second heat sink region, the heat sink structure defines at least a first internal space defined at least in part by the first heat sink region, the second heat sink region and the third heat sink region, the first solid state light emitter is on the first circuit board region that faces away from the first internal space, the second solid state light emitter is on the second circuit board region that faces away from the first internal space, the first fold region is of a rigidity that is lower than a rigidity of the first heat sink region and lower than a rigidity of the second heat sink region, characterized in that: the heat sink structure comprises at least a first heat dissipation element attached to the first heat sink region and extending away from the first heat sink region into the first internal space, the first heat dissipation element comprises at least a first fin element, the heat sink structure comprises at least a second heat dissipation element attached to the second heat sink region and extending away from the second heat sink region into the first internal space, the second heat dissipation element comprises at least a second fin element, the heat sink structure comprises at least a third heat dissipation element attached to the third heat sink region and extending away from the third heat sink region into the first internal space, and the third heat dissipation element comprises at least a third fin element. at least first, second and third heat sink regions (11, 12,13); at least a first circuit board; and at least first and second solid state light emitters, the first heat sink region having a first major surface that extends in a first plane of symmetry, the second heat sink region having a second major surface that extends in a second plane of symmetry, the first plane of symmetry defining an angle of at least 20 degrees relative to the second plane of symmetry, the first circuit board comprising at least a first circuit board region and a second circuit board region, and a third circuit board region, the first circuit board region on the first heat sink region, the second circuit board region on the second heat sink region, the third circuit board region on the third heat sink region, the first circuit board region integral with the second circuit board region, at least a first fold region between the first heat sink region and the second heat sink region, the heat sink structure defines at least a first internal space defined at least in part by the first heat sink region, the second heat sink region and the third heat sink region, the first solid state light emitter is on the first circuit board region that faces away from the first internal space, the second solid state light emitter is on the second circuit board region that faces away from the first internal space, the first fold region is of a rigidity that is lower than a rigidity of the first heat sink region and lower than a rigidity of the second heat sink region, characterized in that: the heat sink structure comprises at least a first heat dissipation element attached to the first heat sink region and extending away from the first heat sink region into the first internal space, the first heat dissipation element comprises at least a first fin element, the heat sink structure comprises at least a second heat dissipation element attached to the second heat sink region and extending away from the second heat sink region into the first internal space, the second heat dissipation element comprises at least a second fin element, the heat sink structure comprises at least a third heat dissipation element attached to the third heat sink region and extending away from the third heat sink region into the first internal space, and the third heat dissipation element comprises at least a third fin element. the heat sink structure comprises at least a first heat dissipation element attached to the first heat sink region and extending away from the first heat sink region into the first internal space, the first heat dissipation element comprises at least a first fin element, the heat sink structure comprises at least a second heat dissipation element attached to the second heat sink region and extending away from the second heat sink region into the first internal space, the second heat dissipation element comprises at least a second fin element, the heat sink structure comprises at least a third heat dissipation element attached to the third heat sink region and extending away from the third heat sink region into the first internal space, and the third heat dissipation element comprises at least a third fin element.