Rubber Ear Mold Buds for Acoustic Tubes are soft, flexible ear molds available in both left and right sides across three sizes. Regular replacement of these ear molds and acoustic tube is key for maintaining optimal audio performance and hygiene. To avoid risk of infection caused by pathogens, bacteria, micro-organisms and various forms of staph, changing ear molds once a month is recommended and sharing of ear pieces should be refrained. Medium is the most popular size, but a Sample Ear Mold Kit including all sizes and an acoustic tube can be considered for uncertainty.