AAA (3+1 Free Pack). Energizer Ultimate Lithium batteries are the worlds longest lasting battery for high tech devices. These AAA batteries hold their power for up to 20 years in storage and weigh 1/3 less than standard alkaline batteries. . Leak proof construction. Weighs 1/3 less than standard alkaline batteries. Performs in extreme temperatures from -40°C to 60°C. Pack of 4