Keep the air inside your home clean and pure with this awesome deal! Right now, Best Buy has this Shark Air Purifier 4 with Anti-Allergen Multi-Filter Advanced Odor Lock for only $199.99! (Reg. $349.99) The Shark Air Purifier 4 with Anti-Allergen Multi-Filter uses Clean Sense IQ technology to constantly track air quality & auto-adjust power. It purifies air with 4 powerful fans and anti-allergen HEPA filtration with advanced odor protection.