This is an authentic Karcher replacement hose designed for high-pressure washers. This hose transports soap from the detergent tank and carries it to the manifold assembly. A filter is built into the hose to prevent contaminants that might enter into the manifold from backing into the soap container. High-pressure hoses are extremely durable. However, they experience more wear, jostling, and stretching than any other part of the pressure washer. As a result, they occasionally need to be replaced. One symptom that the filter is no longer functioning to watch for is dark clouding in the soap. If soap appears on the exterior of the washer manifold or pure water only jets from the pressure nozzle, this is another sign that the hose needs to be replaced. To preserve the hose, soap tank, and internal workings of the pressure washer, it is essential never to use bleach in the detergent tank. Bleach is a highly corrosive material that will quickly ruin the washer. The high-pressure spray will also fill the air with droplets of bleach, which is a hazardous chemical to inhale. This hose is designed to fit more than a dozen pressure washers. It is an OEM certified part, manufactured to the exact specifications of the original hose. Part sold individually.