SATCO Lighting S11973 13W T8 U-Bend LED, 50000 Hours, Medium bi-pin Base, 2000 Lumens, 5000K, Type A/B, Ballast Dependent or Ballast Bypass13 Watt T8 U-Bend LED - 50000 Hours - Medium bi-pin base - 2000 Lumens - 5000K - Type A/B - Ballast Dependent or Ballast Bypass - Single or Double Ended Wiring