I'm looking to connect a NG BBQ I just bought. My house already has the gas line for it. However, when I try to connect the gas line from the BBQ, it doesn't quite fit in. It's a close fit but I don't know what it won't "snap" in. Please see the pics below:

I just got home with my new natural gas BBQ. I though I had a gas line all ready to hook it up to, but I was wrong. Here's what I want to hook it up to: The BBQ comes with what I assume is a standard hose, adapter and quick disconnect coupling. What do I need to do to get these to...