On wildland fire incidents finding power for your battery charger can be problematic to say the least. With a AA battery clamshell you can load 8 AA batteries and keep right on working. Slide the alkaline battery case open to accept (8) AA batteries, then close the case and use the loaded clamshell, just as you would the original OEM battery. AA Alkaline batteries discharge at a higher rate than rechargeable batteries under high current usage, such as keying up your radio. This means that clamshells discharge rates are even more difficult to calcullate than rechargeable batteries. Under a 5/5/90 duty cycle the clamshell loaded with brand new quality AA alkaline batteries will last about as long as a 2,200mAh rechargeable battery, but those same AA batteries loaded into a clamshell and put into service on a radio that undergoes a 10/10/80 duty cycle will only last about as long as a 1400mAh rechargeable battery.