Everbuild 401 Brick and Patio Cleaner (5 Ltr) is a fast-acting, acid-based formula that dissolves mortar stains, ingrained dirt, paint, and algae on most mineral surfaces. Ideal for brick, stone, concrete, paving, and earthenware. Cleans patios, driveways, garage floors, and facades. Economical, 5-liter size covers approx. 10 sq m per liter. Water-based cleanup. This cleaner has a 9.5% acid strength.