I've used a lot of different tire levers, and most simply don't work very well. The Kool Stop levers are by far the best I've tried. The design secret that makes them so effective is a thin but strong tip, that easily slips under a tire bead, and then stays there. The shape works so well that I routinely use just one lever, and zip tires off the rim (and using a second or third lever makes tight tires easy to work with). An absolutely great product at a great price.
These are okay for the price. My main problem with this are that the ends that go between the tire and the rim and this kinda sharp plastic edge You can kinda see it in the photo. I accidentally sliced my tube with it. Ended up sanding the edges and it works better. I would pay a few more bucks for some better levers
I have tried a variety of tire levers and had less than good experiences when they snapped in two.
Then I bought the SPORT levers (before Kool Stop bought them) and they perfect. No scratches on the rim, easy to use and pack into a convenient holder. They are made in Holland, which is a country of cyclists, so they had better be good.
I own several of these sets. Over the years I have used a variety of levers. These are strong, sturdy and reliable. I have not broken one yet. I ride with one set and bought extras for each of my sons so they have there own cycling repair kits.
I have used many different tire levers over the years. The park tool ones I have broken on a stubborn tire, but the koo stop levers have done the job over and over and over. I carry them with me all the time in my commute bag and trust them that if I get a flat, they'll get the job done.
The Kool Stop had a winning, simple design developed a long time ago and it just works. Nothing has changed even with the advent of new rim designs and materials and these plastic levers don't damage carbon. They just work !
These are plastic tire levers, but don't let that fool you! They are really durable and light weight. Haven't had a problem yet with these. Very easy to carry along with you. Don't get caught without them.
I purchased these not expecting to use them more than for an emergency back-up in my travel pouch. Since I couldn't find my other tools I used these and was surprised at how well they work. Being plastic they also keep the rims from being scratched as well.