a heat dissipation element 12 and at least a filler element 13 in the present embodiment there are two base elements 11 and as the two are identical only one is described as follows the base element 11 is radially configured a number of slots 111 along its circumference each slot 111 is embedded with a heat dissipation element 12 and therefore the number of slots 12 determines the number of the heat dissipation elements 12 each heat dissipation element 12 contains two identically shaped pieces arranged in parallel the two pieces are bended along their inner edge to form perpendicular sections 121 respectively the filler elements 13 have the same width as that of each slot 111 the number of the filler elements 13 is the same as or a multiple of the number of the number of slots 111 in the present embodiment there are 15 slots the number of filler elements 13 therefore can be 15 or 30 the length of each filler element 13 is determined by the distance between the two base elements 11 in the present embodiment there are 15 filler elements 13 each heat dissipation element 12 with its two pieces and their perpendicular sections 121 form a u shape with a storage space in between the two base elements 11 are vertically arranged with an appropriate distance and with their respective slots 111 aligned then each heat dissipation element 12 is fitted in a pair of aligned slots 111 a filler element 13 is subsequently inserted into the storage space in each heat dissipation element 12 as such there are gaps between the heat dissipation elements 12 thereby achieving enhanced convection as shown in fig3 and 4 the base elements 11 are further configured with bolt holes through.