The Classic III uses 3M's tunable technology allowing you to transition seamlessly between hearing low and high frequency sounds by simply adjusting the pressure applied on the chestpiece. The double-sided chestpiece allows suitable use on adult and paediatric patients, and features a single-piece diaphragm that's easy to attach and clean. The Classic III offers improved resistance to both the skin's natural oils and alcohol with it's single-lumen tubing, which is latex-free and contains no phthalate plasticisers. The headpiece is adjustable and has soft-sealing eartips for the highest comfort.