Part of the new 18V STANLEY® FATMAX® V20 Cordless System - power all your V20 tools with a common new and improved 18V Lithium Ion battery to let you power through work with ease. PART OF THE NEW 18V STANLEY® FATMAX® V20 CORDLESS SYSTEM: Power all your V20 tools with a common new & improved 18V Lithium Ion battery to let you power through work with ease.