To start out my introduction Rcs Systems are used to menuver aircraft or spacecraft through space these systems are called RCS which stands for Reaction control System
There are many fuel types out there but the one used on the Apollo series of spacecraft was monnopropellant which was a combination of Nitrogen Tetroxide And Monomethyl Hydrazine. This is the basic fuel composition of these thrusters.The other type of fuel for these thrusters are liquid fuel from the main rocket itself thes thruster are a newer versions and are great to use in a spacecraft. The most modern type of thrustr is ones that expel gas to creat propulsion to turn th spacecraft.