Purchased a set of 4 of these in late 2017 to replace the 10 year old ones on my Corvette that were starting to fail. They were a perfect match to the original ones installed at the factory. I was very pleased by this supplier since the ones that I purchased indicated that they were only 1 year old from date of manufacture. These all have a month and year of manufacture molded into the plastic housing and I've heard of people who bought them from eBay or other suppliers and had the batteries in them fail in a short period of time due to their physical age at the time of purchase. I read of one instance where the purchaser found out that they bought sensors that were already 10 years old according to the manufacture code.