I bought two of these to support a 16/18” X 74” x 3 1/2” shelf below our TV. There will be less than 100lbs supported total, but I wanted sturdy brackets that matched the heft of the shelf and these worked great.
On a side note: My brackets arrived slightly damaged cosmetically due to a box failure, but Iron Supports treated me right when I contacted them. Spot on customer service! I’d definitely do business with them again,