Kendall 935 Series Foam Conductive Adhesive Hydrogel EKG Electrode, Radiolucent, Tear Drop, Adult, 1.75". - The high quality foam substrate conforms easily to skin to ensure electrical contact for consistent tracings. - Conductive adhesive hydrogel maximizes adhesion and electrical contact; designed to stay fresh up to 45 days after opening package. - A lift tab located on one edge facilitates easy removal from release liner and patient. - Designed for superior performance including adult stress, holter and diaphoretic applications. - DEHP free, mercury free, not made with natural rubber latex.