The DEWALT DCMCS574 XR FlexVolt Chainsaw has an energy efficient brushless motor for longer run time. Being battery powered, it requires less maintece than a petrol chainsaw, and has an auto-oiling system that keeps the chain lubricated. It also has a tooled chain tensioning system built to professional specifications, this helps to ensure that the chain remains reliably tensioned during use. The chain speed has been optimised for improved torque and a chain brake stops the chain in less than one second if triggered. Specification Bar Length 45cm Chain Speed 13.5m/s. Chain Pitch 3/8in Weight 5.0kg