Ear wax guard is designed to keep ear wax, dust, grease and moisture away from blocking the hearing aids. It needs to be replaced from every week to every month, depends on the ear canal condition. Different people have different ear canal conditions. The filter should be replaced BEFORE it is full of ear wax or dust. Or the speaker of the hearing aid will probably be blocked. HOW TO REPLACE THE WAX GUARDS 1. Take a stick out from the box. The top of the stick is empty for removal, and the end of the stick has a new wax filter for replacement. 2. Insert the removal top into the original wax guard, then slowly rotate and pull the wax guard out, then drop it. 3. Now gently insert the stick end with new wax guard filter into the hole that just lost its original wax guard. 4. The new wax guard will automatically dismount from the holder and remain in place. But sometimes you might need to help separating the new ear wax guard from the stick by your nail. 5. You could also refer to the picture guide as showed above.