To remove the enhancer, pinch the edge opposite of the sound tunnel between your thumb and forefinger and firmly pull up and off the ear bud. Replacement enhancers are specific to the left and right ear bud. An (L) or (R) and size indicator is located on the inside of the enhancer. When changing the enhancers, you must place the right enhancer on the right ear bud and the left enhancer on the left ear bud. Firmly grasp the earbud with one hand and align the sound tunnel of the enhancer with your other hand and stretch the enhancer up and over the top of the red earbud. Check the alignment of the sound tunnel to insure best sound performance. If sound is muffled or weak, check and rotate sound tunnel. Most people use the same size for Right and Left but it is possible to use different sizes because some ears are not symmetrical. - If you’re unable to find a secure fit with both sizes in the box, we can send you a complimentary sizing pack with two additional sizes. Please email ua.jblsupport@harman.com to request yours today.