To see what Stihl model saws we offer a Bark Box for, please check the drop down box on the Bark Box product page. If your model is not listed, it is not compatible with a Bark Box. In order for a Bark Box to be compatible, a two-piece muffler is required. Most often, if your saw model is not listed, it is because the saw has a one-piece muffler. The second reason is that the muffler on the saw is too small. In that case, we recommend opening up the stock hole.