A heat spreader comprising: a) a first planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a first plane of the first planar element and in a thickness direction of the first planar element and having a relatively low thermal conductivity in a direction of second lateral dimension of the first planar element, the first planar element having a first side which extends in a direction out of the first plane of the first planar element and a second side which extends in the direction of relatively high thermal conductivity of the first planar element, b) a second planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a second plane of the second planar element and in a thickness direction of the second planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the second planar element, the second planar element having a third side which extends in a direction out of the second plane of the second planar element and a fourth side which extends in the direction of relatively high thermal conductivity of the second planar element, wherein at least a portion of the first side of the first planar element which extends in a direction out of the first plane of the first planar element adjoins at least a portion of the third side of the second planar element which extends in a direction out of the second plane of the second planar element, and c) a third planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a third plane of the third planar element and in a thickness direction of the third planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the third planar element, the third planar element having a fifth side which extends in the direction of relatively high thermal conductivity of the third planar element, the fifth side of the third planar element adjoining the second side of the first planar element and the fourth side of the second planar element, and the orientation of the direction of relatively low thermal conductivity of the first planar element and second planar element is at a different angle with respect to the direction of relatively low thermal conductivity of the third planar element. a) a first planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a first plane of the first planar element and in a thickness direction of the first planar element and having a relatively low thermal conductivity in a direction of second lateral dimension of the first planar element, the first planar element having a first side which extends in a direction out of the first plane of the first planar element and a second side which extends in the direction of relatively high thermal conductivity of the first planar element, b) a second planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a second plane of the second planar element and in a thickness direction of the second planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the second planar element, the second planar element having a third side which extends in a direction out of the second plane of the second planar element and a fourth side which extends in the direction of relatively high thermal conductivity of the second planar element, wherein at least a portion of the first side of the first planar element which extends in a direction out of the first plane of the first planar element adjoins at least a portion of the third side of the second planar element which extends in a direction out of the second plane of the second planar element, and c) a third planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a third plane of the third planar element and in a thickness direction of the third planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the third planar element, the third planar element having a fifth side which extends in the direction of relatively high thermal conductivity of the third planar element, the fifth side of the third planar element adjoining the second side of the first planar element and the fourth side of the second planar element, and the orientation of the direction of relatively low thermal conductivity of the first planar element and second planar element is at a different angle with respect to the direction of relatively low thermal conductivity of the third planar element.