This is a Genuine DeWALT 18v Circular Saw DUST EXTRACTION+Fence Fits DCS391 Type 1, 10, 11. It is a high-quality guide fence that is perfect for use with circular saws. The fence is designed to fit DCS391 models and has a manufacturer part number of 381091-01 + N104672. The fence is made in Germany and is a great addition to any construction tool collection. This accessory is perfect for those who are looking to enhance their circular saw's performance. It is made by DEWALT, a trusted brand in the industry, and is a great fit for the DCS391 model. The fence is easy to instal and use, and is sure to provide a reliable guide for your circular saw.