The cateye rapid x2 rear bike light is very similar to cateye39s rapid x light however it offers double the output for increased visibility the light still manages to keep the slim form but by upgrading led and battery cateye have squeezed a massive 50 lumen output from this slimline light don39t be fooled by the design though this light still offers 360 degree visibility and it has a burn time of up to 30 hours to ensure the light doesn39t run out of battery when you39re