The Premium R40P.4 is the ultimate vacuum for allergy sufferers. A seven-stage filtration system with a HEPA Plus media filter, HEPA media vacuum bag and granulated charcoal filter ensure no dust escapes into the room, and odors are contained. The self-sealing bag prevents you from coming in contact with all the dirt the vacuum has removed. Even when you can't see deep-down dirt, the R40P can. Its dirt sensor lets you know when dirt is still hiding in your carpet so you can vacuum the gritty particles before they damage carpet fibers. This vacuum's Hall Sensor stops the brushroll when it senses a jammed condition. Then it's simple to remove the offending object and restart the vacuum, which means no more broken belts. Bag and filter sensors gently remind you when your vacuum needs attention.