1、REPLACEMENT: BTE hearing aids can become uncomfortable as the ear tube gradually hardens and will need to be replaced. 2、: The sound tube is made of high quality PVC material, which is not easy to harden and is sturdy and durable. 3、BASIC PARAMETERS: The eardrum sound tube of the hearing aid is formed in R shape, with an outer diameter of 3 mm and an inner diameter of 2 mm. 4、EASY TO REPLACE: No need to go to the audiologist to replace the tube, replace the tube yourself, saving time and money. 5、WIDELY APPLICABLE: The sound tube of hearing aids is easy to install, effectively transmits sound, and is suitable for most hearing aids. Item Type: Sound Tube Material: PVC Size: Outer Diameter: Approx. 3.0mm/0.1in Inner Diameter: Approx.2.0mm/0.08in 10 x Sound Tube