Features: 1.OE Number: The referencing OE number of this ignition coil are 1140 1305 B and 1140 400 1303, which is molded and designed depend on the original chainsaw data. 2.Fitment: The engine ignition coil is a replacement for Stihl MS311 MS391 MS311Z MS391Z, please check your chainsaw model before ordering. 3.Function: Improve combustion efficiency and enhance electrical performance. Provides a higher intensity spark with faster recovery and response, increased ignition energy intensity. 4.Premium Material: The ignition coil is made of heavy duty steel which is sturdy and durable, helps to provide easy starting and smooth operating. 5.Easy Installation: You need to remove the original broke or damaged igniter inside the chainsaw and install the ignition coil in the same way. Specification: Item Type: Ignition Coil Kit_x000D_ OE Number: 1140 400 1303, 1140 1305 B_x000D_ _x000D_ Material: Steel_x000D_ Fitment:_x000D_ Replacement for Stihl MS311 MS391 MS311Z MS391Z Chainsaw Note: Please double check the part number of your item, matching information is for reference only._x000D_ If you are unsure of the item, please contact us before buying to avoid unnecessary return, thanks!