The STIHL 40057102100 AutoCut 40-4 is a genuine OEM mowing head designed for efficient cutting with STIHL brushcutters and clearing saws. This robust mowing head is equipped with a double line for mowing and clearing work, making it ideal for tough grass and weeds. It features a convenient 'tap and go' mechanism for easy line reloading by tapping the head on the ground while running. The AutoCut 40-4 is compatible with a range of STIHL models, ensuring optimal performance and durability for professional and demanding home use.