As others have said, the rear bristles are too long to be effective. Even tilting your nose forward doesn't help. I trimmed the sides and back of this attachment along its frame, also trimmed the front a bit and now it works fine. To get a straight cut, point the scissors in toward the frame. I have a 2.5hp 5 gallon vacuum, not the most powerful unit in the world but for home use it's fine with a regular bag installed. Modifications may not be needed for those with a more powerful vacuum.
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