This genuine Toro OEM 15 lbs cast weight kit is designed for Toro GrandStand stand-on mowers and adds ballast to improve front traction and stability when mowing slopes, hills, and uneven ground. Insufficient front weight on a stand-on mower can cause the front caster wheels to lose contact with the ground on steep terrain, reducing steering control. Adding a weight kit is one of the most practical at-purchase accessories for operators who regularly mow on sloped properties. Verify your model and serial number before ordering.