Crystal Water Filter - For Cars and Windows - 25 Litre INSTALLATION & USE Mains water contains impurities and salts which leave spots and smears on paint after washing. Some of this will be due to scale caused by Calcium and Manganese. A water softener will remove Calcium and Magnesium and therefore preventing scale formation.  However some impurities remain and if you want a spot and smear free finish on your paintwork then our specifically designed car wash filter is the best for this.Our filter has been specifically designed to provide ultra-pure water for the washing of cars and windows. Inside the housing is a special media which removes all impurities from water. This means that when water evaporates on paintwork or glass, no spots or streaks are left behind , leaving you with a perfect finish.The filter can be connected to your hosepipe. As the media has a finite life, we suggest using it for a final rinse, though you can use it for the whole car washing process. The media wi