Hi, I've been to USA in aircraft a few times in the past and never had to use one of these "Airsafe plugs".

They are designed to isolate the batteries on Mobility Scooters.

I know Li-On batteries have to be carried inside the cabin with the scooter user, we have a scooter with Lead Acid batteries which have always been allowed to remain on the scooter inside the luggage hold. 

We have one of each type of scooter now and may have a second with Li-On battery for myself. (Those Disney parks are massive and too far for an old fart like me to walk around, especially when another two in the party are razzing round in the scooters ha ha).

Any info would be greatly appreciated.

Thanks.