Simpson Strong Tie ETB6 Steel Hole Cleaning Brush, 3/4" x 4" (16" Total Length) 3/4-inch by 4-inch brush (16-inch total length) 3/8-inch to 5/8-inch anchor/rebar diameter 1/2-inch to 3/4-inch hole diameter 3/4-inch by 4-inch brush (16-inch total length) 1/2-inch to 3/4-inch hole diameter