Compatibility: Compatible With Shark Detect Pro Cordless Stick Handheld 2-In-1 Lightweight Vacuum Models Iw3511, Iw3120, Iw1111, Iw1120 | | Package Contents: You Will Receive 1 Pack Back Hepa Filter And 2 Pack Prefilters | | Easy To Install: Effectively Prevent Dander, Dust, Hair. Improve The Surrounding Air Quality And Protect Your Health. We Recommend Replacing Filter Every 3-6 Months To Extend The Lifespan Of Your Vacuum Cleaner | | High Quality Material: Our Hepa Filters Are Of High Quality And More Durable. Made Of High-Strength And Environmental Protection Material | | Please Do Not Hesitate To