The REDLITHIUM™ Extended Capacity Battery Pack (sold separately) delivers more work per charge and more work over pack life than the competitors, as well as best-in-class performance in extreme jobsite conditions. You'll get consistent speed control between 0-1900 rpm and 0-2200 ipm with the variable-speed trigger. The 2662-20 has a 1/2 in anvil with detent pin to ensure maximum socket retention. The M18™ Impact Wrench's onboard, real-time battery fuel gauge helps you monitor the charge precisely, so there's less downtime on the job. Lightweight and portable, with superior ergonomics, this 18 V cordless power tool offers ultimate comfort during prolonged use.