Stihl Trim Cut 31-2 cutting head with 2.4mm line. This Stihl Trim Cut replacement head has double line for mowing & thinning grass. The nylon line is adjusted by h&. The replacement trimmer head will take pentagonal, round or square 2.4mm cutting line. To fit Stihl models: FS56, FS87, FS90, FS100, FS130, FR130 T, FR 480 C-F Only approved for use with a guard