ITEM NAME:Universal Fit Trimmer Head ABS M10 x 1.25 Grass Brush Head Cutting Lawn Mower.Thread size: M10 x 1.25. Mounting: Thread hole size: M10 x 1.25 Left Rotation Way. Less 30 second line twist loading--easy load system, no disassembly required. Simply feed the line into the eyelet, give the head a twist and it’s ready to go.