: Snap the roof ridge hooks' T-bars against the eaves or other grooved areas to provide extra security against tilting or falling ladders. : Made of rust and heat resistant steel, a pair of roof hooks for ladders can hold over 500 lbs (250 lbs each) with a rust resistant finish. : The ladder ridge hooks are designed with four mounting holes, you can choose the most suitable mounting holes according to the spacing of your ladder to meet your needs. : The grip T-bar is wrapped with rubber to prevent wear and tear on the roof and also increase the friction to provide more stable support. In addition, the universal wheel design can be more easily moved and placed on the roof. :For the top 2 rungs of the ladder and hooks on the edge of the roof,mounting hardware included.