Direct Replacement Part: This replaces part numbers 4009 710 2106 and C3-2, ensuring compatibility with for Stihl FSA 57 and for FSE 52 models from 2020 onwards. Designed for seamless integration, this head restores performance. Compatibility and Performance: Specifically designed for Stihl FSA 57 (2020 On) and for FSE 52 (2020 On) weed eaters, this C3-2 features a bump and feed mechanism that automatically feeds the nylon line with a simple tap action. Advanced Feeding Mechanism: The C3-2 operates with a bump and feed system where the nylon line is fed automatically by tap action. This feature enhances ease of use and efficiency, making your trimming tasks quicker and smoother. Versatile Line Options: Compatible with 2.0mm or .080inch diameter line, this double line is ideal for both trimming and mowing tasks. It offers flexibility in line choice, adapting to various grass types and conditions. Colour:BlackandWhite Material:plastic Package Contents: 1 x C3-2 (The color of the rope is random, no specified color is accepted) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.