This stethoscope includes the thicker dual lumen tubing and not the thinner one tube to both binaural as seen on non-cardiology stethoscopes. This allows for better sound as well as insulating from background noises. The dual lumen tubing in one design means there is a separate tube coming off each binaural. This allows for the greater acoustic response from the stethoscope head. Unique design that combines the acoustic response of a traditional bell and diaphragm into an advantageous one-sided chest piece. The bell-type low-frequency response is achieved by simply holding the chest piece in place with light pressure. Diaphragm retaining rim for patient comfort. Compare to other bi-lumen cardiology stethoscopes and I do not think you will find a better value anywhere. Overall length 27" Weight 7.5oz. We include 2 extra sets of ear tips and a spare diaphragm. We will always stand behind our products. You will not be disappointed with how well this stethoscope works at this price