A bundle packed with replacement parts compatible with both the Utillian 721, 722 and 723. The kit includes 5 screens,2 magnetic cap o-rings, and 2 mouthpiece o-rings. These parts are used to maintain your device's hardware. If you find your device working less efficiently, take a look at these parts and if they are in need of replacement. Compatibility Utillian 723 Utillian 722 Utillian 721 Package Contents 5x Screens 2x Mouthpiece O-Rings 2x Magnetic Cap O-Rings