All the lawn service folks here seem to use a circular attachment/upgrade that makes their straight shaft string trimmers into very effective edgers (no blades, just the string). The thing basically looks like an industrial strength big metal pie plate that shields the trimmer head and slides along the sidewalk or bed edge. I found them for sale on some website last year, but I dawdled in replacing my perfectly good curved shaft trimmer, and now I can't find the gadgets again.

Anyone know what this is and where I can get one?