Stainless steel construction for rugged durability. Combination chestpiece precisely machined to exacting tolerances for outstanding acoustic performance. Extra deep bell for unsurpassed low frequency response. Non-chill bell and diaphragm ring for patient comfort. Custom molded 16 bi-lumen PVC tubing improves acoustic separation. Internal spring construction reduces bulk. Binaurals fixed at 15 angle for greater comfort. Includes one pair of plastic eartips and two pair of PVC eartips with threaded metal inserts for the ultimate in wearing comfort and acoustic seal. Weighs 9 oz. Overall length 25. Latex free. Lifetime warranty.