Echo & Shindaiwa Genuine Part 69500121431 is used on models SRM-300AE Straight Shaft Trimmer-SRM-300AE1 Straight Shaft Trimmer-SRM-302ADX Straight Shaft Trimmer-SRM-200D Straight Shaft Trimmer / Brushcutter-SRM-202DA Straight Shaft Trimmer / Brushcutter-SRM-202F Straight Shaft Trimmer / Brushcutter-SRM-202FA Straight Shaft Trimmer / Brushcutter-SRM-3800 (Type 1) (001001-040446) Straight Shaft Trimmer-SRM-3800 (Type 1) (After S/N 040447) Straight Shaft Trimmer-SRM-3800 (Type 1E) (After S/N 001001) Straight Shaft Trimmer-SRM-400 (03001001 - 03999999) Straight Saft Trimmer Brushcutter-SRM-400 (04001001-04999999) Straight Saft Trimmer-SRM-400BE Straight Saft Trimmer-SRM-400U (03001001-03004773) Straight Shaft Trimmer-SRM-400U (04001001 - 04001494) Straight Shaft Trimmer-SRM-400U (S04703004774 - S04703999999) Straight Shaft Trimmer-SRM-400U (S16004001495 - S16004999999) Straight Shaft Trimmer-SRM-400U (S16103004774 - S16103999999) Straight Shaft Trimmer-SRM-4600 Straight Shaft Trimmer-SRM-300 Straight Shaft Trimmer / Brushcutter-SRM-3000 (After S/N 043226) Straight Shaft Trimmer / Brushcutter-S-2P-SRM-3000 (001001 - 021090) Straight Shaft Trimmer / Brushcutter-