The FLEXVOLT 60V MAX* Chainsaw features tool-free chain tensioning and combination tooled/tooless bar retention knob to enable proper bar clamping force. It also features a high-efficiency brushless motor to help maximize run time and motor life and auto-oiling for continuous lubrication. This kit includes a FLEXVOLT 20V/60V MAX* battery that powers 60V MAX* tools or it can be backwards compatible to work with 20V MAX* tools.