Designed by a roofing contractor, the Safe T Climb is a completely universal extension ladder anti-fall device, said the company. It is designed to work on any ladder and on any flat or pitched roof, or parapet walls. The kit comes with parapet legs that work on 6-to-8-inch walls. Extra-reach parapet legs are available to accommodate up to 14-inch walls. According to the manufacturer, the device can be installed in less than a minute to positively prevent the ladder from falling.