These Duracell D alkaline batteries are perfect for devices with long-life, powerful energy consumption like motorized toys, flashlights, CD/DVD players, etc. The D (mono) batteries are most often used in high current drain devices such as large flashlights, radio receivers and transmitters, boomboxes, Geiger counters, megaphones, or other applications that require an extended running time.Duralock technology kept unused Duracell batteries fresh and fueled for up to 10 years. Package includes two D batteries.