Scrubbing Bubbles Automatic Shower Cleaner Refill can make the tough job of cleaning your showers easy. What is great about this cleaner is that it attacks soap scum. It also works to clean molds and mildew stains. This cleaner helps you to maintain the shower for at least a month. With this cleaner you don't have to clean your shower too frequently because it works for up to 30 days. You will receive two refill bottles. These will only work with scrubbing bubbles automatic shower cleaner.