The steel these clamps are made of is too brittle for spring steel. I broke three by simply clamping them when they were about to be installed. After installation, three of the four clamps broke the next day, which I was able to install intact. Garbage. I used them on a Tygon fuel line and PVC hose. 2 different clamp sizes, same results. Unreliable in use even if they survive installation. waste of money and time. Of the 10 clamps used, 6 failed. I used another product to complete the job.