Trip-pod head, quick release and lock?

[BraindG]

Hi all,

I'm looking to buy a new head for my tri-pod, but I'm trying to figure out what heads have the quick release and a locking nut, could someone please advise what the locking nut is called, the bit that secures and tightens the quick release plate into the head?

For example i think this 054 Magnesium Ball Head with Q5 Quick Release has one, once I know what that locking bits called i'll be ok

I've had to many sets of images ruined because the current quick release I have moved a little when checking exposures.

Thanks
Bary

 

[tijuana taxi]

Arca Swiss are the standard Q/R arrangement found on many tripod heads

Look like this http://www.kirkphoto.com/SQRC-Arca_Arca_Swiss_Quick_Release_Clamp.html