you need a battery, maybe a flexible pushrod if you want it for your throttle, but you should see i the arf has a straight shot throttle linkage first. nitros do not need a speed control, they emerged above that level a LONG time ago. all they need is an actuator of some kind, to move a throttle linkage to open/close the carburator barrel.
you will also need fuel lines, and i dont konw if it supplied in the kit or not.
on top of that, there are plenty of optional things you could put on there, but that is really a case by case type of thing.
is this.
you asked about the speed control on gas engines. does this mean that your PTS is electric?