The active use portion consists of (1) a web browsing test accessing 8 popular websites over multiple open tabs, (2) a productivity test utilising Microsoft Word, PowerPoint, Excel and Outlook, and (3) a portion of time with the device in use with idle applications. Testing consisted of full battery discharge with a mixture of active use and modern standby. Testing conducted by Microsoft in April 2020 using preproduction software and preproduction configurations of Surface Book 3 13.5” Intel® Core™ i5, 256 GB, 8 GB RAM. Surface Book 3 13.5” on base: Up to 15.5 hours of battery life based on typical Surface device usage. *Some accessories and software sold separately.