The Black & Decker CS1830B-B1 vacuum cleaner uses intelligent sensor technology to effectively clean your home. There are three smart sensors. The floor sensor automatically adjusts the suction power when you move from hard floor to carpet. The filter sensor allows you to know when it's time to clean the vac and maintain suction power, and the battery sensor tells you how much battery remains before recharging. It's a smarter way of cleaning your house with this vacuum cleaner.