MODEL NUMBER:W10491331 Dishwasher Lower Wash Arm Assembly，Replacement Arm Compatible with Maytag, KitchenAid, Jenn-Air, Amana, Magic Chef, Admiral, Norge, Roper, and Kenmore/Sears brand appliances models . The dishwasher lower spray arm is an replacement part responsible for distributing water and detergent to clean dishes and utensils in a Whirlpool dishwasher. It consists of a rotating arm with spray nozzles that emit pressurized water, ensuring even coverage and effective cleaning of the dishes. This part fixes the following symptoms: (1)Inadequate cleaning performance or poor washing results. (2)Food particles or residue left on dishes after a wash cycle. (3)Uneven water distribution or weak water pressure during the wash cycle. (4)Spray arm not rotating or spinning properly. (5)Clogged or blocked spray nozzles. The spray arm works in conjunction with the dishwasher's water pump and motor to propel water and detergent onto the dishes, removing food particles and stains.