MTD-compatible lawn tractor mower blade holder hub shaft Length (mm): 139.7 Blade holder (mm): star 6 teeth Weight: 309 g For models: MTD U 845 H , RMS 18-117 , RMS 18/117 Part No.: 13289539 Original part No.: 618-0117B , 618-0117A , 618-0117 , 918-0117 , 618-0112 MTD