no problem...we also have them here in metal. It is the best thing IMO for concrete walls. We have the same type of construction for houses here. Houses are made with concrete block and we use fischers for everything. Different sizes and different types of different jobs is all. We have the wall mount for our 40 hung with fischers and it is completely secure. Just ask Frost and Vega. They have made a grand journey across the top of the hanging TV.