The 79.0111 blade is a mulching blade designed to maximize mulching performance by finely shredding grass clippings and evenly distributing them across the lawn. This is achieved by cutting the grass multiple times before it ever leaves the deck. This is a Ventrac Genuine part provided specifically as a blade option for the MS600 60" Discharge Mower when equipped with a mulching kit.(A quantity of 3 blades is required for this deck).