The Makita 198386-5 Trimmer Bump & Feed Trimmer Head is a replacement cutting head designed for compatible Makita string trimmer equipment. It works by holding and dispensing trimmer line, allowing the cutting line to extend as needed during operation. The bump-feed design allows the user to advance the line by tapping the head against the ground, helping maintain an effective cutting... https://www.wholetoolbox.com/makita-198386-5-trimmer-bump-feed-trimmer-head/198386-5.html