3M™ Futuro™ Comfort Lift™ Knee Support, Large, 1 Box of 3 Penlights blisters and itching commonly associated 18747 blisters and itching commonly associated with poisonous plants 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 Beige color may make support less visible under light color clothing Large size is for knees 17 to 19½ inches in circumference