Propane inline Tee

[ksmoody]

I would like to install a brass propane tee on my rig between the tank and the regulator to connect a BBQ.
I don't know what type of thread connection to get. I have seen ones that are POL or ACME thread. I don't know the difference between those two types.
I have a 2008 Fleetwood Tioga.

[enblethen]

Best thing to get is this:
Extend a flow
You can find just the tee at some Ace Hardware