The futaba battery checker is one like he was saying to use becuase it checks batterys under load. But I disagree with him about running your batterys down to 4.6 volts thats a good way to lose your plane when the battery goes dead, 4.8 volts is the lowest I would go. Yes you can buy a higher amp pack up to around 4000milliamp hours, but a battery between 1500 and 2000mah should be a good battery for you.

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