Samaritan PAD Pak Adult replacement cartridge has a 4 year shelf life from date of manufacturer.? This includes one set of defibrillation pads and a battery which incorporates one expiration date for easy maintenance. Provides over 6 hours of continuous monitoring or 60 shocks. ?? The Adult (Grey) PAD-Pak™ is for patients > 25kg normally over 8 year old to adult (55lbs) The Pediatric PAD-Pak™ (Pink) is for patients over 1 year to 8 years old and under 25kg (under 55lbs) The Replacement Trainer PAD-Pak is designed only for use with the Samaritan PAD training units. Cartridges can be used with the HeartSine® samaritan® PAD Models 350p, 360p & 500P. Please note, these are UK/Ireland specification items and adhere to the MHRA and IMB guidelines.Replacement HeartSine Samaritan Pad-Pak which is compatible with all current HeartSine AED\'s including the 350p, 360p and 500p. The normal shelf life of the Pad-Paks is over 3.5 years.