The Whirlpool WP99002135 Stop-Rack keeps the dishwasher rack securely positioned by helping prevent it from sliding beyond its intended travel point. This replacement component attaches to the designated rack or rail area, acting as a stop that limits movement and helps keep the rack properly aligned during loading and unloading. A functioning rack stop supports smoother rack operation and reduces the risk of the rack coming off its track during everyday use. If the original stop is broken, loose, or missing, the rack may move too far or become difficult to handle.