Outstanding Acoustics Are Combined With A Unique And Easy To Grasp Chestpiece That Allows Easy Movement Between Auscultation Sites. Single-Sided Chestpiece Provides Both Bell And Diaphragm Frequency Responses. Dual Lumen Design Helps To Eliminate Noise Artifact. Comfortably Angled, Anatomically Correct Headset. Patient-Friendly, Nonchill Rim. Six-Year Warranty.