Lawn-Boy 21 inch Self-Propel Rear Wheel Drive Mower is a great value. Backed by one of the best warranties in the industry, it's easy to handle and hard to beat. The rear-wheel-drive self-propel design provides power for improved traction and control in all mowing conditions. Kohler XTX OHV engine series engines bring lawn care to a new level. Commercial-Grade features deliver tough performance and operator-centric design provides user-friendly maintenance. 3-In-1 Discharge Ability Lawn-Boy's versatile cutting system allows you to choose between mulching, bagging, or side discharge. 3-Year Tru-Start Commitment plus a 2-Year Full Warranty Under normal use and maintenance, it will start on one or two pulls for three years or we will fix it for free.