Echo 215607 Bump Feed Trimmer Spool CAUTION !!! This is a 2 slotted spool, it will only replace a 2 slotted spool This only has one chamber for trimmer line not two Fits: 21560050 ECHOmatic Head, 99944200230 Semi-Auto Dual Line Head, 99944200540 Grass Trimmer Attachment S/N: S06400001001-S06400999999, 99944200545 Pro-Torque Trimmer Attachment S/N: S08900001001 - S08900999999, SRM-2100 Type 1 S/N: 001001 - 159490, SRM-2100 Type 1 S/N: 159491 - 999999, SRM-265T S/N: S66011001001 - S66011999999, SRM-265T S/N: S70511001001 - S70511999999, SRM-265T S/N: S73511001001 - S73511999999, SRM-265T S/N: S79812001001 - S79812999999, SRM-265T S/N: S81013001001 - S81013999999