As a hesitant buyer, I purchased these screws for an industrial project. As a result of my tests, I determined that they were completely inadequate. The screws stripped easily and had a weak grip, making them unusable for my purposes. It's frustrating that these screws are still being sold in the Industrial and Scientific category, as they are nothing but a waste of time and money. The only pro is that they come in a pack of 100, but that doesn't make up for their poor quality. Steer clear of these screws!