has substantially vertical wall 25 surrounding open space 12 edge 21 is shown as having edge 210 curled inwardly for finished appearance open space 12 has a centerline 14 shown in fig5 and heat dissipating surfaces 41 are fins 410 extending away from centerline 14 fig3 4 7 and 8 show fins 410 extending radially away from centerline 14 in an embodiment illustrated in fig3 6 fins 410 extend away from centerline 14 to terminate in distal edges 43 spaced from inner surface 23 of housing 20 fig1 shows an embodiment of lighting fixture 10 including heat sink 40 c which has fins 410 extending away from centerline 14 to terminate in distal edges 43 at inner surface 23 of housing 20 it is seen in fig1 that light emitting arrangement 30 is substantially stabilized on centerline 14 fig3 5 6 and 8 show a centerer 50 which holds light emitting arrangement 30 substantially on centerline 14 such centering of light emitting arrangement 30 facilitates fluid flow along heat sink 40 and through open space 12 fig5 and 6 show light emitting arrangement 30 substantially free of contact with inner surface 23 of housing 20 it is further seen in fig3 5 and 6 that centerer 50 is disposed between light emitting arrangement 30 and housing 20 centerer 50 as best seen in fig3 and 8 includes brackets 51 each secured with respect to light emitting arrangement 30 each bracket 51 has a mounting portion 52 secured at light emitting arrangement 30 and at least one leg portion 53 extending from mounting portion 52 to a free end 54 at inner surface 23 of housing 20 it is further seen in fig3 5 6.