The Ryobi 5-1/2 in. 18T Thin Kerf Carbide Circular Saw Blade is a high-quality and durable tool designed specifically for circular saws. With a blade diameter of 5 1/2 inches, this black carbide blade is perfect for making precise and clean cuts. The set includes one saw blade, making it convenient for users to have a spare on hand for their power saw. This product is a reliable choice for those in need of a durable and efficient cutting tool for their workshop or gardening projects.