Certain hard surfaces may require more intense cleaning to get the job done. While you could use a 0 deg pencil jet spray nozzle, that method can be very time consuming. Karcher's turbo nozzle takes a 0 deg nozzle and rotates it at high speed, giving you the effective cleaning power of a pencil jet but with a wider area of cleaning. This greatly speeds up the task of deep cleaning hard surfaces. Fits Karcher and most other brands of pressure washers rated up to 4000 psi. Quick connect.