Zero-Turn Mower 42 in. MulchControlT Kit for Z300 Series. The Mulch Control Kit for the 42 in. Accel Deep Mower Deck makes mulching more practical for many mowing situations. It not only does an excellent job of mulching but it also allows the mower to be easily converted when it is more desirable to side discharge or bag. Turn Mulch Control on with the flip of a lever when you want to mulch, turn off Mulch Control 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.