Formed, elastic medical grade material for sensitive skin. This product is sent out assembled with the thin tube and ZipTip. Please specify Right or Left and the size of the thin tube (#1, #2 or #3). Thin sound tubes for The Encore hearing aid is available for both ears in varied lengths and sizes, made of medical-grade material suitable even for the most delicate skin.This accessory fits the following devices: Otofonix Encore Hearing Aid