Glass water repellent makes the glass hydrophobic: water pulls into beads and clears faster as you drive. It also improves visibility and makes driving safer.
Kickdown is a long-lasting silicon dioxide coating that lasts up to 12 months and needs the glass prepped first. Before you apply it, remove water spots with the abrasive glass polish Lime Scrub, then prep the surface and apply the product with an applicator pad.
Rain Drops is a fast spray-on glass water repellent that needs minimal surface prep. Just prep the glass, spread the product evenly over a dry, clean surface and buff off after 10–15 minutes. For both products, water starts to sheet off at 35 mph and up, depending on the angle and condition of the glass.
Why isn't the water repellent working?
With Kickdown, the most common reason is poor glass prep. Even glass that looks clean can be covered with mineral deposits from hard water, road film or remnants of an old coating. As a result, the glass water repellent doesn't bond with the glass properly and never forms an even hydrophobic layer.
Cleaning the surface completely before you apply is key. To remove mineral deposits and old coating residue, you can use Lime Scrub. After that, rinse it off with a pressure washer, wipe the glass dry and prep it with Easy Prep.
One more factor matters for both products — the condition of your wiper blades. A worn or damaged blade can wipe the coating off in a few weeks. So replace old wipers before you apply.
Which glass water repellent should you pick: Kickdown or Rain Drops?
Kickdown — if you're ready to spend an hour on prep and want results that last up to 12 months. Rain Drops — when you need to quickly refresh water beading without complicated prep; it lasts up to 3 months.
At what speed does water start to clear?
Both products start shedding water at 35 mph and up. The exact result depends on the condition of the glass, the quality of your prep, how evenly you applied it and the angle of the surface. You can see the effect at lower speeds too: water beads up and the wipers clear the glass more easily.
What should you use to prep the glass before a water repellent?
For prep, you can use Easy Prep. Apply it to a clean, lint-free microfiber towel and wipe the glass thoroughly. If the surface has a white haze from hard water or leftovers of an old glass water repellent, remove them first. Use Lime Scrub for that, then rinse the product off, dry the glass and only then do the prep. The main principle is simple: clean the glass first, then prep it, and only after that apply the glass water repellent.
Do you need to rinse the water repellent off, and how long does it take to cure?
No need to rinse: 10–15 minutes after application, buff the product off with a clean, dry microfiber towel. After that the coating needs time to cure on the glass: first contact with water is no sooner than 8 hours for Kickdown and no sooner than 3 hours for Rain Drops. Wait at least 7 days before washing the car with chemicals.
Does a glass water repellent damage wipers?
The opposite: both products extend blade life. Treated glass gets slicker, so the rubber can move across the surface more easily.
Why did my wipers start chattering after I applied the glass water repellent?
There can be a few reasons: worn wiper blades, no factory glide coating left on them, weak arm pressure against the glass. Try applying the glass water repellent to the blades themselves — in some cases that does the trick. Prep the rubber with Easy Prep and apply the repellent to the wiper blades. If that doesn't help, replace the wipers.
Can you apply glass water repellent to film?
No. Both products are made for glass, and we don't recommend applying them to films.
Can washer fluid or winter washer fluid strip the water repellent?
Regular glass cleaners and washer fluids won't strip a glass water repellent — these products are highly chemical-resistant. The coating does wear down from mechanical contact, though: frequent wiper use thins the layer over time, so the repellent gradually loses effectiveness.
How do I apply glass water repellent in two layers?
The windshield gets two layers. After the first layer you don't have to buff it off. Give the product its dwell time — 25–30 minutes for Kickdown, 10–15 minutes for Rain Drops — then apply the second layer. After 10–15 minutes, buff off the surface.
Which microfiber towel should I use to buff off glass water repellent?
A clean, dry, lint-free microfiber towel. From our lineup, Pearl Wipe and Terry Wipe work well.
How should I apply glass water repellent: in circles or in a crosshatch pattern?
The main thing is to spread the product evenly over the whole window, with no missed spots. Crosshatching works best: go side to side first, then up and down.
How long does glass water repellent keep once it's opened?
Six months or more. It depends on how long the bottle sat open and how much the product was exposed to air, so cap it right after you're done.
