The brackets are very very heavy. Thick steel (good strength!), 4'6" long and over 10' at the wall-end. The lag bolts included seem too short and light to hold all that weight. The installer is buying much larger lag bolts. Either way, the bolts need to go into a structural part of the building, not the siding. I believe that, once installed, work and look beautifully. I'm pleased with the quality.