There are several Type B (ballast bypass) HID LED replacements, but GE's is unique for a couple of reasons. For one, it is the most efficient out there with lumens per watt ratios of 150+. The biggest factor is that GE designed these lamps to be the same size and form factor of their metal halide/high pressure sodium counterparts. Other LED brands provide lamps that are often times too big to fit within the same fixture. Rated for 50,000 hours with a 5 year manufacturer warranty. Rated for open or enclosed fixtures. Damp rated. Available in 4000K and 5000K. Lower watt options available in E26 base and E39 base. Tether kit and in-line fuse included which provides 6 kV surge protection