For precision sanding, buffing and cutting, HART's 20V Rotary Grinder Tool is the way to go. It delivers 5,000 to 34,000 RPM with the variable speed dial for control.
HART 20-Volt Cordless Trim Router Kit for Cutting, Shaping and
20V 4-1/2 Brushless Cordless Angle Grinder (Battery and Charger
Hart Tools Launches New Line of Tools at Walmart - Tool Box Buzz
20V Rotary Grinder Tool (Battery and Charger Not Included) - HART
20V Cordless Multi-Tool (Battery and Charger Not Included) - HART
HART 20-Volt Brushless 4-1/2-inch Angle Grinder/Cutoff Tool
20V Precision Craft Rotary Tool Kit - HART Tools
20V Rotary Grinder Tool (Battery and Charger Not Included) - HART Tools
20V Rotary Grinder Tool (Battery and Charger Not Included) - HART
Hart 20-Volt Cordless Rotary Tool with 33 Accessories Kit
20V Rotary Grinder Tool (Battery and Charger Not Included) - HART