The Efco 320010021 is a genuine Double Start Star Tap'n Go trimmer head designed for Efco brushcutters and trimmers. Featuring an M10x1.25 LH (Left Hand) thread, this robust head is compatible with cutting lines ranging from 2.4 mm to 3.0 mm in diameter. Its Tap'n Go mechanism allows for quick and easy line advancement, ensuring efficient operation. This universal head is ideal for maintaining various Efco models requiring this specific thread type, offering reliable performance and durability.