The manufacturer told me to order STAINLESS STEEL Tapcon screws to attach a pressure treated 2x4 to a concrete block exterior wall due to prolonged exposure to moisture was. I used a compressed air spray can to get all the dust out of the hole when installing the bolts. I also used a few drops of 2" x 4" Loctite PL construction glue. Something like belts and suspenders. Use an impact wrench to tighten most of the way, then do the final tightening by hand. The work turned out great!