NADAC “Gates”?

Anyone ever hear of “gates”?  On the NADAC’s website they have Gates listed as an obstacle.  And it has a 2009 date as if its something new, or going to be new.  It’s definitely  new to me.  I know it’s for a class called “Gaters”, but I’ve not yet seen the class done, nor what the gates look like.  Anyone have any pics???   From: http://www.nadac.com/Rules_for_NADAC_trials.htm#_Agility_Obstacles