Coral 27  * Two tunable diaphragms conveniently alternate between low and high frequency sounds without the need to turn over the chestpiece * Solid stainless steel chestpiece * 27  tubing * 2-in-1 tube design eliminates tube rubbing noise * Excellent acoustic seal and comfortable fit with patented Littmann Snap Tight soft-sealing eartips * Comfortably angled  anatomically correct headset * Patient-friendly  nonchill rim and diaphragm * 5 year warranty