AS REQUESTED,  CUSTOM .156 OD (4MM) GLASS TUBE SLIM PIGTAIL (WITH LEADS) VU TYPE LAMPS FOR YOUR AUDIO NEEDS. SOME AUDIO APPLICATIONS (ESPECIALLY METER LAMPS)REQUIRE  SMALL OD LAMPS TO FIT IN NARROW SPACES. THESE LONG LASTING  HIGH OUTPUT LED CIRCUIT REPLACEMENTS HAVE AN AVERAGE LIFESPAN OF 100,000 HRS.THE AVERAGE INCANDESCENT BULB LIFESPAN IS 1000 HRS. CIRCUIT AND LEDS (2 LEDS PER LAMP) DRAWS ONLY 15 MILLIAMPS AS OPPOSED TO THE ORIGINAL INCANDESCENT 30 TO 40 MILLI AMPS SO HEAT IS NOT A PROBLEM.