Tackle your mowing projects on lawns with hilly or uneven terrain with the Black Max 21-inch 3-in-1 Perfect Pace Mower! Perfect pace self-propelled technology automatically adjusts to the user’s walking speed for an easier mowing experience. The 11-inch wheels and rear wheel drive provide that traction you will need for even the most difficult yard. This mower is equipped with a Briggs & Stratton 725EXI . 163cc engine for ultimate power through demanding applications. The Mow N Stow capability allows you to easily fold up your mower and save up to 70% in storage space. The lightweight . polymax deck is rust resistant. Maximum strength that can only be found at Walmart!