RELIABLE PERFORMANCE: 12-pack of AA rechargeable NiMH batteries (2,400 mAh)DEVICE COMPATIBLE: Ideal for devices with high power or continuous drain like game controllers, wireless devices, toys, and moreLONG LASTING: Can be recharged up to 400 times with minimal power lossLOW SELF DISCHARGE: Maintains 50% capacity for 1 yearEASY USE & STORAGE: Has a shelf-life up to 5 years for everyday or emergency use; arrives pre-charged and ready to useNOTE: To avoid damage or undesired rapid discharge of the batteries, DO NOT MIX: non-rechargeable with rechargeable batteries; fully-charged with mid- to low-charged batteries; new with old batteries; different mAh capacities; different brands.Ni-MH Battery Tips: Verify device compatibility with 1.2V Ni-MH batteries. Runtime may be shorter than 1.5V alkaline batteries. Check proper fit as Ni-MH batteries are slightly larger than alkaline batteries to comply with IEC standards. Replace all batteries simultaneously and consult the device manual for specific requirements.Charger Tips: Use only Ni-MH specific chargers with independent charging channels and voltage monitoring to prevent overcharging or undercharging. Avoid timer-only chargers and never use chargers designed for other battery types (like NiZn or Li-ion), as this may cause damage or leakage.