Unfortunately they have been on my car for a year now and I broke one changing a wheel recently. They were originally purchased in March 2014 and installed shortly thereafter. You could actually see some oxidation on the ledge where it cracked. I was lucky that this happened when changing tires and not while driving. Needless to say I was very disappointed in a product that was supposed to have exceptional durability and strength. The studs were installed by the dealer and I treat my service consistently. This includes air pressure and torque settings. I also use a torque wrench to ensure proper performance. I was lucky enough to have an OEM bolt that fits the hub at my local shop. Unfortunately, these were additional costs. I hope this was a unique scenario but I am very disappointed in the quality of the product and now I doubt the quality of other tips.