The best way to remove the enhancer from the ear bud is to gently pull back the outer rim of the enhancer that is located around the base of the ear bud. When replacing the current enhancers with a different size, please make sure to align the funnel of the enhancer tip over the small speaker screen of the headphone casing. The LEFT enhancer will feature the square cut out that allows you to receive your Heart Rate reading. It is important that the small digital square on the ear bud is fully exposed and the enhancer cut out is placed around it and not over it. If the enhancer is not attached properly, you will hear the audible voice stating that it cannot receive an accurate reading on your heart rate and you will need to readjust the enhancer.