Hushtone 2-Speed Motor: Quickly Toggle Between Less Disruption With Quiet 69 Db Performance And A Boost Mode For Extra Power Extended-Life Belt: Advanced Circuitry Protects Long Lasting Belt By Shutting The Motor Off To Avoid Belt Breakage Sealed Allergen System: Traps 99% Of Dirt. Dust And Pollens Down To 0.5 Microns For Cleaner Air With Hexaguard Technology No Tools Required: Ready To Use Right Out Of The Box. And Air Path Can Be Cleaned In Seconds With No Tools -