The 3M Littmann Master Cardiology Stethoscope features tunable diaphragm technology 3M invention that lets clinicians hear different frequency sounds by simply adjusting the pressure on the chest piece. Unlike two sided models, theres no need to turn over and reposition the chest piece. Hold the chest piece with light pressure to hear low frequency sounds; press a little more to hear higher frequency sounds. This time saving feature allows the healthcare provider to focus on the patient, while the non-chill rim provides patient comfort. Headset tension is easily adjusted for head size and comfort by squeezing together or pulling apart the ear tubes. Snap tight, soft sealing ear tips conform to individual ears for an excellent acoustic seal and comfortable fit. Ear tips snap firmly onto the ends of the ear tubes and, for safety, require a significant effort to remove. Resilient next generation tubing retains its shape and flexibility even after folding tightly into a pocket. It provides longer stethoscope life due to improved resistance to skin oils and alcohol, and is less likely to pick up stains. Next generation tubing is not made with natural rubber latex, a benefit to sensitive medical professionals and their patients. And, to play its part in the protection of human health and the environment, the next generation tubing does not contain phthalate plasticizers. It comes complete with large and small soft sealing ear tips, Special Procedures Adapter, and instructions.