The Scrubblade Wiper Fluid Concentrated Tablets are the most convenient and cost effective way to use and store windshield wiper solution. The tablets are added into regular tap water and can be used in any window or glass surface - house windows, shower enclosures, mirrors Easy to use - add one tablet per one gallon of tap water. Tablet can be pre-mixed in a jug or the tablet can be dropped directly into the washer fluid reservoir Effervescent tablets and environmentally friendly Convenient and cost effective to use and store windshield wiper solution Turns regular water into a window cleaner - can be used in all glass surfaces - house windows, mirrors, shower enclosures Each box contains 5 tablets that make 5 gallons of washer solution