These Irwin Industrial Tool 2084200 20-Count Bi-Metal Blades are a classic and versatile tool for a variety of different projects. They feature the patented Bi-Metal technology that sets new standards of performance and offers long-lasting use. The technology of each of these Irwin blades in blue helps them to stay sharp three times longer than the next-best utility blades. The box includes 20 unbreakable blades so that one is on hand when needed. These utility knife blades are compatible with multiple styles of retractable and fixed knives for ultimate convenience. Use them to open boxes, achieve a precise cut line, scrape off old glue or paint, make small, detailed cuts and so much more. They are compact in size, which allows for easy storage when they are not in use. They come in a convenient carrying container that offers easy access and helps keep them safely organized.