DDU 100 Live Adult Electrodes pack contains one set of adult defibrillation pads for use with the Lifeline AED. These pads are for Adult use only (8 years or older). Pads should be stored connected to the AED. Extra pads can be stored in the available carrying case. These self adhesive pads are non-polarized, so that either pad can be placed in either location, simplifying the rescue. Pads have 2 year shelf life.