The ECHO 8 in. With standard 20mm size arbors, the blade conversion kit fits a variety of ECHO SRM models. ECHO 8 in. 8-Tooth Brush Blade Conversion Kit (20 mm). Compatible with ECHO SRM models: SRM-225, SRM-225i, SRM-266, SRM-280, SRM-280S, SRM-280T, SRM-2620 and SRM-2620T.
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