Review on 🧽 EVERSPROUT Pro Grout Brush Scrubber - Strong V-Shaped Bristles for Corners & Stubborn Grime - Swivel Design for Shower Tiles, Kitchen, Bathroom, and Outdoor Concrete - Convenient Twist-on Attachment (Pole Not Included) by Guillo Tilden

I own Utopia Tile and Grout in San Diego, California who renovate, repair and replace tile, stone and grout. 6-10 (on a scale of 1 to 10) and it's fantastic, except for me it wears off too quickly to use on black grout (it's really white!). The angled (super stiff) bristles make it super easy to stay in. Lay any size grout line and angle it to get at the dirt on either side of the line. It screws onto any standard size broom or mop handle thread so you don't have to buy one. Level 2. I recommend this product even if I pass them quite quickly.