The MTD 753-06805 Trimmer Boom Lower Assembly W/Shaft supports the connection and operation of compatible string trimmer components. This replacement lower boom assembly includes a shaft that transfers rotational power from the upper drive section to the cutting head during operation. It helps maintain proper alignment and stable connection between the trimmer sections, supporting con... https://www.wholetoolbox.com/mtd-753-06805-trimmer-boom-lower-assembly-w-shaft/753-06805.html