3M™ Futuro™ Comfort Lift™ Knee Support, Large, 1 Box of 3 Penlights Designed to help you listen Wall Transformers Designed to help you listen for hard to hear sounds including aortic stenosis S3 gallop murmurs and faint pulmonary anomalies Threaded chestpiece drum of chrome plated zinc permits the use of five interchangeable chestpiece fittings an adult and pediatric diaphragm and three bells (11 4 1 3 4 ) for complete diagnostic capability in most patients * Latex free double tube configuration * Proprietary valve mechanism eliminates acoustic leakage * Adjustable chrome plated brass binaurals * Complete with an accessory pouch containing the bell chestpieces chestpiece key 2 spare diaphragms one pair of mushroom eartips and one pair of silicon eartips * Inspected and packaged in the U Large size is for knees 17 to 19½ inches in circumference Four way stretch and contoured design conforms to your knee for comfort and mild support