The 4ft 18W LED Linear Tube is a high-efficiency glass T8 replacement designed to upgrade traditional fluorescent lighting while cutting energy use by up to 70%. It operates on a ballast-bypass system, meaning the existing fluorescent ballast must be removed or bypassed for proper installation. Built with durable glass construction, the tube delivers bright, consistent, flicker-free i... https://greenlightdepot.com/products/4ft-18w-led-linear-tube-glass-ballast-compatible-ul-type-a?_pos=1&_sid=6b5f7eeec&_ss=r&variant=11328217808939