Pack of 100 disposable patches for use with the ECG sensor. The ECG electrode patches are a silver/silver chloride gel on a foil backing. The gel is hypoallergenic and has adhesive properties that enable the electrode to stick to the skin surface. The foil backing provides a constant area of contact and the gel gives a constant skin electrode resistance. A minimum of three of these disposable electrode patches are required for each test subject. Once a pack of electrodes has been opened they should be stored in a cool place, in a clean dry airtight container.