To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
We installed this on a standard white melamine shelf - the kind you buy from Home Depot that's about 5/8 in thick or so, and also very similar to the one in the product description's picture. One of them immediately broke on the little arm that goes around the shelf to hold it up. The other is still working, but it seems like it'll break if we ever take it off and put it back on. I would not recommend this product. Reporting this more than 30 days after purchase so no way to return it I guess.
These are for thin, shallow shelves, like the shelves in a bookcase. I had to really force the clip down to get it onto my sturdy closet shelf, then when I realized it only covered half of the space from the end of the shelf to the wall, it put a permanent scratch in my shelf as I removed it.