The Oregon 91623 is a high-quality standard lawn mower blade designed for durability and efficient cutting. Measuring 18 inches (457.2 mm) in length and 2.5 inches (63.5 mm) in width, this blade features a 0.203-inch (5.16 mm) thickness, a 5/8-inch (15.88 mm) center hole, and 3/8-inch (9.53 mm) outer holes with a 1-7/8-inch (47.63 mm) center-to-center spacing. It serves as a direct replacement for various OEM part numbers from Scag, Great Dane, and Wright Manufacturing, ensuring a precise fit and reliable performance for compatible mowing equipment.