They do have this
on their web site. Although the lowest test frequency on the chart is 125Hz, the data does look pretty good for the price.
I attached some extra Auralex pieces to the front of mine for an extra couple inches of foam. From what I can tell the foam is identical to the Auralex foam. Both companies are located on the north of Indianapolis. It's obvious that the Cornerblox are cut from a 12x12 inch square piece. I'm thinking of asking if I can get an 8 foot long 12x12 inch square piece to stick in the corner.
I have no affiliation with this company, just use their stuff.