20 WATT MR 16 TYPE BAB BLACK BACK HALOGEN LIGHT BULB WITH LENS COVER - 36 DEGREE BEAM SPREAD - LONG LIFE 6,000 HOURS -  Supra Life MR16 halogen lamps use a quartz envelope for durability and pure tungsten for longer life. The regeneration cycle continuously restores the filament, creating a 6 times longer burning life and clear crisp white light. Nickel end pins resist heat and provide positive electrical contact. Precision reflectors provide excellent light control with a fluted mirror. Dichroic coating removes 65% of the heat by passing it through the back of the lamp, resulting in a cooler light beam ideal for retail displays.