Necessary and practical: just 1 piece car effervescent tablet and 4 liters of water, you will get 4 liters of car windshield glass concentrated washer for you to clean and lubricate windshield, which can reduce the friction of wiper and glass, keep your car windshield in neat and good working condition Advanced Quality - No measuring, no spills, no mess or plastic bottles to dispose of and no storage. Dissolve thoroughly. Note: Please be aware that this is a summer formulation. Temperature Requirement > -5 No Traces/Damage - This car clean washer tablet does not cause damage to the glass surface, helping to maintain the car windshield protective film,which can soften the wiper and reduce noise. It leaves no trace or reflection for more visibility and safety. Clean window and safe driving. Multi-Use - Our multi-functional effervescent tablet is also designed to replace your mirror cleaner, kitchen cleaner, window cleaner, tile cleaner, etc. It is a powerful integrated cleaning agent, not only suitable for cleaning car's glass, but also has strong decontamination effect on kitchen stains, toilet floor stains, etc. Safe for all metal, windshield and window glass, rubber, plastic and painted surfaces. How to apply: you need to put 1 piece glass solid wiper cleaning tablet into the wiper can and pour proper amount of water, or you could dissolve the tablet with a small container, then pour the dissolved cleaning fluid into the wiper can and fill it with water, which could dissolve more quickly and thoroughly