Fangrui Product Details The Inline Filter Is Suitable For Cpap Devices. It Is Used In Combination With The Machines Built-in Inlet Filter To Deliver Very Clean Air. The Outer Diameter Of The Connector End: 25mm. The Inner Diameter Of The Female Connector End: 22 Mm. Suitable For 22 Mm Pipe Making Machine. Installation And Are Quick And Easy. The Filter Is Connected Between The Air Or Outlet Of The Machine And The Cpap Hose. Results: Keep The Air Inhaled By The Cpap Machine Clean For The Therapeutic Effect. A Set Of 6 Filters. Does Not Contain Latex. Each Filter Is Individually Sterilized And Sealed. Material:abs Colour:as Shown Package Contents: 6 X Filters Only The Above Package Content, Other Products Are Not Included. Note: Light Shooting And Different Displays May Cause The Color Of The Item In The Picture A Little Different From The Real Thing. The Measurement Allowed Error Is +/- 1-3cm.