required application length as long as the grouping of assembled components maintain mechanical integrity and an environmental seal referring to fig6 and 9 the led printed wire boards 12 14 are securely fastened to the inner mounting base 10 which provides a heat sink path for dissipating heat generated by the leds 16 the right and left pwb segments 12 14 are positioned such that the leds 16 straddle a center ridge 64 of the mounting base 10 the center ridge 64 of a preferred embodiment acts as a continuous structural support member and efficient heat sink for the leds 16 the leds 16 are placed in intimate contact with the center ridge 64 of the inner mounting base 10 in a preferred embodiment of the invention the leds 16 are cemented to the center ridge 64 using conductive cement to increase rigidity of the leds as well as to provide maximum heat transfer of the heat generated by the individual leds to the inner mounting base 10 as shown in fig1 and 3 the inner pwb mounting base 10 is in intimate contact with an outer support structure and base 28 which provides a further path for heat transfer a base 28 of a preferred embodiment is extruded aluminum for maximum heat dissipation linear cavities 36 in the base 28 provide for the circulation of cooling fluid as necessary fans filters and electrical junction boxes 130 134 as shown in fig1 can be attached at each terminus of the base 28 to force cooling air through the linear cavities 36 and or the cable conduits 38 in the base 28 mounting.