4-Pack of Hyperikon T8 4FT LED Light Tube, DirectConnect, Plug&Play (Operates with newer electronic T8 ballasts ONLY), 18W (36W equivalent), 5000K (Daylight Glow, Dual-End Powered, Frosted Cover, UL-listed and DLC-qualified Cost effective LED plug-and-play replacement of fluorescent tubes. Save up to 50% on your energy bill. This T8 BallastCompatible LED Tube has a lifetime of 50,000 hours (22 years when on 3hrs/day, 365 days/yr) Compatibility - Please note that this tube is tested to operate with modern electronic instant start T8 ballasts ONLY. This tube will not function with T6, T10 and T12 ballast nor with old magnetic T8 ballasts. No tombstone hassle and no professional electrician needed. This tube will provide an instant fit with your current T8 4FT fixture. This T8 LED tube will outlast any ballast by at least 2 times the lifetime of the ballast. Keep in mind that when the ballast burns out it must be replaced to restore the lighting capabilities of the LED Tube. This tube does NOT function without a ballast. Please see Hyperikon BallastCompatible Hybrid 2.0 if you're looking for a tube that can operate both with and without a ballast.