Let’s try a different one
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Will do what ya need. Just widen the hole by wiggling the auger around in the hole if it's too small. But I think the auger bit it comes with will suffice.
I personally use it professionally, be sure to use 2-stroke (weed eater) oil in the gas. 50:1 ratio. I've dug 100's of holes, had it catch on roots, concrete, bricks, etc. It works perfectly. The clutch saves your wrists if it does catch, though it's not exactly gentle.