This Mulch Control kit is compatible with Z515E and Z530M with 60 in. Accel Deep decks. It allows the operator to mulch with the flip of a lever. When the baffle is closed, the mower is set to mulch mode and will circulate the clippings, cutting them into finer pieces. When the baffle is open, the mower is in discharge mode, allowing clipping to escape. Flip Mulch Control on when you want to mulch. Turn Mulch Control off to side discharge or bag. It is an innovative design that is easy to use and maintain. Advantages include reduced debris in unwanted areas, less fertilizer use required and elimination of the need to dispose of clippings.