Replacement for Toro 3521 421 521 Snowblower Skid Shoe set of Two 40-8060-01
Set of 2 SkidsReplaces Toro part #  40-8060-01Quality Aftermarket Skid shoe set fits Toro 3521 421 5215/16" slots X 1-5/8"  2" on center5" long and 2-3/4" wide