It is suitable for cutting lawns, around trees, between shrubs along edges, walls and fences. Easy loading by inserting the line into the eyelets and turning the knob AutoCut C6-2/C5-2 Replacement Trimmer Head Replaces OEM Part Number: 4006-710-2126, 4006-710-2106 Bolt Adapter Size: 10mm x 1.25 LHF, can use 2mm diameter line Compatible models: Stihl FSE60, FSE71, FSE81, FS38, FS40 (since 2008), FS45, FS46, FS50