Hi,
You will need a plug and lead to go from the aircraft power to the ANR power supply.
You should be able to get a techo to make you up one that plugs into the aircraft mil spec 24 Volt 2 pin socket (that is usually installed on the Bells). Just remember to have a "break-away" connection (plug) near you helmet in case of emergencies.
Batteries; In a 412 my rechargable 9Volt battery lasts about 5 hours. I converted the battery box for the ANR kit to take 2 x 9 volt batteries in parallel. This will double you useable time. If using the rechargeable type 9V, get the "no memory" ones so you can flatten them completely and then recharge them again. This set up for me typically lasts about 2 years before replacing the batteries.
If you can get a 2nd battery box, do the same set up and you can swap boxes in flight when one goes flat.
It takes about 17 hours to recharge the batteries.
Once you have ANR it is very difficult to fly without it.
Have fun!
Cheers, 800