mechanically pressure resistant walls or preferably is filled and sealed tightly by being filled or potted with a thermally conductive electrically non conductive insulator material this material such as an epoxy insulator 21 extends at least from the juncture of the lamp support 11 and the container 18 see fig1 b and fills the interior of the container 18 around the ballast 13 and any related electronics to eliminate vacant spaces within the container 18 this material also serves to extract heat away from the ballast 13 so that the ballast container and the material serve as heat sink means the ballast container 18 can be in the nature of a mold which once the potting epoxy has solidified may optionally be removed the potted thermally conductive electrically non conductive insulator mass 21 surrounds or substantially surrounds the ballast 13 and any related electronic components and extends rearward e g to the right in fig1 from the lamp support 11 and along the ballast input 20 the ballast input 20 is preferably coupled to a standard type of connector see fig7 and fig8 described below so that the lamp and ballast assembly 10 may be retro fitted to an existing lighting.