After cleaning the sound bore, hold the new tube against the earpiece canal and gauge approximately where you want the tube to end in the sound bore. Clip the tubing straight across. Note: It is very important that the tubing be cut at 90 degrees to the tube sidewall.
Pour a small amount of tubing cement (thin cement for acrylic earpieces, vinyl cement for vinyl earpieces) in to a small cup or bowl.
Note: The following steps must be performed quickly. Familiarize yourself with all of the steps before you begin:
Dip the end of the tube into the cement. Tap the tube against the sides of your cement container until only a small amount of cement remains in the tube end.
Place the tube over the sound bore. Pinch the tube and quickly insert it into the sound bore. Pinching the tube causes the cement inside the tube to coat the wall of the sound bore, acting as a lubricant during tube insertion and then securing the tube when it dries.
Make sure the tube is at the proper angle and allow to dry. The earpiece is now ready to be refit the hearing instrument.