Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Requires Expensive Backing Plate

This may or may not be a good product from a usage standpoint, but Amazon and no one else apparently makes it clear that the product is useless without a velcro backing plate that costs another $20. They even try to sell it as an add on to a polisher without the backing plate!!If you want to use this pad with your polisher and it does not have a velcro backing plate, you will need to buy one.