LiPo Receiver
#2

You can run without a regulator but it's not "recomended". I say recomended because I have run lipos with both of my buggy and truggy using JR 9100's all year and only broke 1 but dont think it was from over voltage. If you use a regulator, Castle, Losi , Orion and KoPropo make good ones. If you use one, make sure it gets some airflow across it to keep it from shutting off.