Echo 99944200422 8 in. 8-Tooth Brush Blade Conversion Kit for SRM TrimmersEcho 99944200422 8 in. 8 Tooth Brush Blade Conversion Kit for SRM Trimmers Echo blade conversion kits offer more versatility with your Echo SRM trimmer. From trimming the lawn to cutting through dense weeds and underbrush, our blade conversion kits deliver convenience and unit flexibility. With standard 20mm size arbors the blade conversion kits fit a variety of Echo SRM models. Kits come with or without a brush blade so you can customize your trimmer