SATCO Lighting S18452 13W T8 U-Bend LED, 50000 Hours, Medium bi-pin Base, 1900 Lumens, 4000K, Type A/B, Ballast Dependant or Ballast Bypass13 Watt T8 U-Bend LED - 50000 Hours - Medium bi-pin base - 1900 Lumens - 4000K - Type A/B - Ballast Dependant or Ballast Bypass - Single or Double Ended Wiring