This is a refill for Muc-Off BIKE CLEANER 500ml concentrate. It is the item shown in the third photo. Diluting the 500ML package with water creates 2 liters of cleaner. It can also be used as a concentrate, in which case it functions as a powerful degreaser, effectively removing dirt from chains. Made with the latest nanotechnology that breaks down dirt and dust at a microscopic level, its cleaning power is astonishing. It contains no dangerous acids or chemicals, is biodegradable, alkaline, and gentle on both bikes and the environment. Safe for all bicycle parts and surfaces, including carbon fiber. It will not damage seals, cables, brake pads, or rotors.