The S9500 Custom Ear Insert comes in a Three Pack, inclusive of one small, one medium, and one large insert. The S9500 Custom Ear Inserts are compatible with the HKLN4601 surveillance earpiece. The ear insert replaces the earbud which ships standard and adds a whole new level of comfort for customers wearing earpieces for extended periods of time. The S9500 Custom Ear Insert fits into your ear and rests on the inner ridge of your ear canal. Made out of pliable silicone, this product is super comfortable and costs a fraction of what traditional custom earpieces do. Installation is easy. Simply remove the standard ear bud included with your HKLN4601 and insert the plastic elbow into the flat side of the ear insert. Apply a little force and push the elbow in until it is flush. It's that simple. Note, the narrow tube rests in your ear. The Ear Tip should not be used by multiple employees as it may come into contact with ear wax. As a result of the personal use of this product, it may not be returned once opened.Motorola