To shift or flex. This term applies to our fence panels (not gates) which have the ability to be shifted on site to follow the contour of a slight slope, medium slope or steep slope or stairs. The homeowner/business owner or installer has the ability to do this on site prior to installation. Racking is but one of many benefits to using our products; we have a fencing system that gives you the ability to install our fence panels on a hill or slope. The easiest way to determine is to look at each 6 foot run on your property and determine whether or not you have a rise or fall of more than 6 inches PER 6 FEET. If so, then you’ll need to configure some of your panels rackable. If not, then you can configure your panels: “Standard.”