This screen is used for measurement of the content of chunky fibers in GP or MP. With MP, chunky fibers may cause a problem in the paper machine's plate section or during the drying process. Structurally, this equipment is like the No.2625. The difference is that this screen is provided with an injection nozzle at the center of the screen, through which clean water is flashed at a certain pressure onto the plates of the screen box, preventing clogging of the plate grooves and achieving superior screening.