The Toro 107-3709 Lawn Mower Geared Rear Drive Wheel 8" helps provide smooth and controlled movement for compatible lawn mowers during operation. Designed as a geared rear drive wheel, it works with the mower’s drive system to transfer movement to the wheel and assist with forward travel. A properly functioning drive wheel supports steady traction and maneuverability while mowing. https://www.wholetoolbox.com/toro-107-3709-lawn-mower-geared-rear-drive-wheel-8/107-3709.html