These are ACDelco 800mAh NiMH AAA batteries, that will give you 4 times more durability than regular batteries. We believe you will be satisfied with this selection. Thank you, Powermax USA
Whatever the headset's specifications are, that's what you should go with. You can always go higher in a non-recharging device, such as a headset, but, going lower can affect the sound quality, as well as wear out the battery, sooner.