Wen Rotary Tool Flex Shaft The Wen Rotary Tool Flex Shaft is great for getting to those awkward jobs. At first I thought it was a gimmick but it does work. The Flex tool runs smooth and quiet. The shaft can heat up fairly quickly so you may have to use it for short periods before rest. Source: https://rotarytoolsguide.com/wen-2305-rotary-tool-kit-review/