Oil, filter and tire changes are taken for granted as periodic maintenance necessities. Others, as wiper blade replacement, are more often neglected until their declining function forces attention. But your dimming headlights are such a gradual process that it's easy to go completely unaddressed though degraded lighting poses a real safety threat. The clear plastic covering the headlights is exposed to chemicals splashed up from the road surface and acid rain which is constantly baked on by the intense heat of modern bulbs. Oxidation happens until it looks like it's wrapped in wax paper and your headlight beams are severely compromised. This kit and 20 to 30 minutes of your time can render those lenses crystal clear and looking like new.  The instructions note that you will need to have access to an electric or battery powered drill.  The kit comes with a disc pad holder that fits into the drill. Small circular sandpaper discs are attached to the pad via a velcro-like backing. There are supplied several discs of 500 grit, 800 grit, a "trizak" disc for further polishing, a foam pad and and a small amount of polish/rubbing compound cream.  Before beginning work, the area around the headlight needs to be protected with recommended masking tape. 3M Kits I'd purchased in the past included this tape, but this particular kit does not.  (Kit #39014 also sold on Amazon includes 25' of tape but costs about $7 more. If you already have suitable masking tape from a painting project you can save a few dollars with this kit though.)  I used blue masking tape found in big box home supply stores in the painting section.  Two layers are recommended to assure no damage happens to the adjacent car body paint surrounding your headlights.  Once taped, the lens should be washed with soap and water to remove any dirt. Attach the first disc and with light to medium pressure go over the entire lens, making certain not to stay in one spot too long which would heat and damage the plastic. You might feel some uncertainty and wonder if you're destroying your lenses because they become a milky white. Be certain to periodically pat the disc to remove any residue dust buildup. When you have a consistent surface, move on to the next finer grit, the white 800 disc. This refines the surface though still an opaque white. The lens should be wet with a spray bottle or damp cloth and kept wet while using the Trizak disc. Finally use the foam pad attachment with dime sized amounts of the polishing cream. It's best to put the cream at the center of the disc and then slide it around the lens before you turn on the drill to have an even distribution and less spatter.  If you don't rush through the process and do each step completely, you should now have headlights that look completely new. I've used perhaps 5 of these kits over time and the results are consistently amazing. There are kits that are easier to use with only fluids you apply by hand and elbow grease. They work ok, depending on the degree of residue and oxidation you have to remove. But if you want a professional looking restoration and you have a little patience, this kit provides outstanding results. Just be certain to purchase the necessary masking tape and try not to rush through the process.