I just bought an '07 H3x. There's nothing in the owner's manual about the roof rack. It appears you can move the bars back and forth, but there are what look like locks built into the pillars. I didn't get any keys for these, are they a standard item I can buy? Or am I visiting a locksmith?

 

On the circular lock area, right where you insert the key, there will be stamped numbers, SP1, SP2, SP3, SP4 or SP5.
That's the key code needed. You can get them from a GM dealer or put a "wanted" ad in the classified section below for the key that you need.