ADC Adscope 655 VistaScope, Adult Lightweight Stethoscope with Interchangeable Designer Diaphragms, 31.5 inch Length, Black Diaphragm only type chestpiece fabricated from lightweight acrylic provides up to twice the amplification of conventional acoustic scopes No electronics to malfunction, no batteries to wear out. lightweight scope is neither bulky nor awkward to use Stainless steel binaurals with double leaf internal spring fixed at a 15 degree angle for greater comfort, reinforcing yoke molded into flexible 22" pvc "y" tubing Adsoft delux pvc eartips in small and large sizes for the ultimate in wearing comfort and acoustic seal. metal threaded retaining ring. scope id tag included Eight printed designer diaphragms included for peronalizing