Item Type: Cerumen Stop Filter Material: ABS Aperture: Approx. 2.5mm / 0.1in Suitable Hearing Device: Suitable for Siemens hearing device Usage: Take out the old wax guards with net feeder, clean horn mouth, stuck the other end of with net feeder, then install into horn mouth, gently test whether it is firm and not loose Package List 1 x Storage Box 8 x Cerumen Stop Filter 1. Clean wax guards often with a small brush2. Replace wax guards half a year to a year according to earwax condition3. After installing wax guards, make sure it is firmly installed to avoid falling into ear canal 1Water and Oil Resistant: These wax guards are waterproof and oilproof, so you do not have to worry about water and oil corroding and staining guard filters. 2Preserve Hearing Device: Effective protection and maintenance of hearing device to avoid frequent replacement or breaking or damaged, extending the life of hearing device. 3Effective Cleaning: Most hearing device and listening devices can be cleaned in detail. And is convenient to install and use, even for the elderly. 4Prevent Foreign Objects: Prevents earwax, dust, oil, and moisture from clogging the hearing device, which can avoid affecting function of hearing device. 5ABS Material: Wax guards are hard, impact resistant, scratch resistant, and dimensionally stable, but also moisture and corrosion resistant to ensure long term durability.