Here you will find support wings that fit most hearing aids on the market. The important thing to remember is to choose a support wing that fits your hearing aid. A support wing is a supplement to keep the sound tube in place and is an option if you find that the sound tube often falls out of your ear. It may also be worth considering whether you have the right size domes, as small domes can also cause the sound tube to fall out of the ear.
It's quite rare that you need to replace it, but if you find that your current support wing has stiffened or broken down, it may be time to replace it. Often you can cut the support wing to the desired length, so it fits comfortably and holds the sound tube in place.