Makita GD0801C 1/4-Inch SJS Die Grinder Electronic Controller for Operator Convenience Powerful 6.6 AMP motor delivers 7,000-29,000 RPM for faster material removal Super Joint System - SJS technology helps prevent motor and gear damage by allowing the drive shaft to slip if the wheel is forced to a stop Variable speed control dial enables user to match the speed to the application Constant speed control automatically applies additional power to the motor to maintain speed under load