Arnold Universal 20-Inch 3-in-1 Mulching Lawn Mower Blade If you want your outdoor power equipment to last longer and do more you want Arnold parts accessories and attachments. Providing you with a wide variety of top-quality snow-friendly products Arnold winter parts and accessories will get your equipment through those cold snowy months. Compatible with tons of major brands 50+ years of proven performance has landed Arnold a reputation of cutting edge product innovations and extensive engineering expertise. From basic maintenance to major innovations Arnold has everything you need to keep equipment running the way it should season after season. With Arnold you can be confident of a reliable product with accurate fit design material and construction. In addition to reliable parts and accessories Arnold?s easy-to-follow instructions and extra tips will ease your equipment maintenance and assure that you get the job done right. Size: 20 Universal 3-in-1 blade 2 sizing washers allow this blade to fit mowers with 3/8 & 7/16 diameter center hole hub 3/8 7/16 & 5/8 universal center hole with HOP/Toro adapter Includes sizing washers and cover washers