You didn't say use for what. Most likely you will need some kind of an adapter, depending on the unit you want to install it on.
tekme is the best place to look (or print your own).
9/16 connector on it is for the BO/ADV reg inside - yes you need an OPV on the 1st.
I haven't seen the service kits available. I service mine with the dealer - I would recommend the same, at least in the beginning. I think they need some special tools, although not 100% sure about it, talk to your nearest dealer, I'm in the EU and it's easier for me.
An important point - it's not just a BOV. It's a BOV/ADV.
Something I would recommend if you're ok with shutoffs in general - is putting one right at the 9/16 connector. This BOV doubles as the ADV and in normal setting it's enough to look even slightly down and it will blow up your loop if you have BM CL.
At the very best it's annoying and wastes the dil, at worst in some pinch it might start a chain reaction and pull you up.
You need to include the shutoff operation in your S drill, as I've seen someone BO and then grow big eyes and almost panic as they forgot about the shutoff.
But overall I love this BOV, how small, light and streamlined it is, angle of the loop connection, the fact that in a pinch it doubles as the ADV and when it does - it blows the gas straight into your mouth. Very useful for loop flush with no hands.
I am connecting my stage to it using QC6 instead of dilout, gives me more peace of mind in case of CO2 hit, but it's not common practice.
Dislikes - some were released with leaks from factory and need a rebuild by the dealer, a simple service won't help. I hope yours is not one of those. Also without the shutoff it basically blocks you from looking down or any head-down position or it will blow your CL up and pull you out.
