It measures 3/4" clearance between the carpet and the bottom of the bracket. In my case, in addition to the thickness of the carpet (which is thin), there's a layer of Dynamat as well as a layer of 1/4" Dynaliner. The Planted brackets are pretty typical for mounting Recaros I think and there'll be maybe a little more room by the time you add the seat adjuster plus whatever open cavity there is in the bottom of the seat. Hope that helps...