What size string for stihl fs56 weed-eater?

The Stihl FS56 weed eater typically uses 0.080-inch (2.0 mm) diameter string for its cutting head. However, it can also accommodate 0.095-inch (2.4 mm) string, depending on the specific model and head attachment being used. Always refer to the operator's manual for the correct specifications and recommendations for your particular unit.