From a squared set: Face corner, walk past corner (men on the outside), give a right hand to opposite (as in Right and Left Thru), pull by, pass the next person left shoulders, then meet partner across the set for a courtesy turn to face the middle. Finishes in a squared set. (The call used to be directed to the men as "Go outside two and inside one and courtesy turn the next one, son").
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.