The Adscope® 641 Sprague features:Threaded chestpiece drum of chrome plated zinc permits the use of five interchangeable chestpiece fittings - an adult and pediatric diaphragm, and three bells (1 1/4", 1", 3/4") - for complete diagnostic capability on most patients Double tube configuration, not made with natural rubber latex Proprietary valve mechanism eliminates acoustic leakage Adjustable aluminum binaurals Convenient 22" tubing length in 31 model options Complete with an accessory pouch containing the bell chestpieces, chestpiece key, 2 spare diaphragms, and one pair of silicon eartipsOverall length 30" 5 Year Warranty Inspected and packaged in the U.S.A.