The STIHL AR 2000 backpack battery was made with professional landscapers in mind. It delivers exceptional run times – up to 11 hours with the HSA 66 hedge trimmer. Built-in sensors and microprocessors monitor temperature and automatically shut down the battery if it overheats. The backpack battery also includes an ergonomic hip belt and chest strap that evenly distributes its weight. And in light rain, the included removable rain cover keeps crews powering through their task at hand.