Amazon offers its Prime members the GreenWorks 25302 G-MAX 40V Twin Force 20-inch Cordless Lawn Mower for $283.50 shipped. For comparison, it originally sold for $399 but usually goes for around $340 these days. We did see it hit $260 once at Amazon. The GreenWorks 40V lineup offers a solid combination of power and capability. This mower includes a 20-inch deck, dual blades and two batteries plus a charger. Over 2,500 Amazon customers have left a 4.1/5 star rating.