Product Description: 10"x10"x2" wide x 0.25" thickness, Granite Countertop Support. It has 3 holes of diameter 0.26" in flange-1 and 3 holes of diameter 0.39" in flange-2. 

Product Uses:  The heavy duty 1/4"  L bracket is designed to be used for attaching granite countertops to walls or kitchen islands.  The steel angle has mounting holes for easy assembly using screws or bolts.  This steel angle mount can also be used for standard shelves mounted to walls.  The heavy duty fabrication of these brackets make them perfect for tough applications.  Your granite countertops are valuable make sure you use high quality Short Run Pro counter top mounts to support them