Steve, That was my post on THT. I posted on this site too minus the pictures. I explained here what is causing this issue according to the owner of the company that makes these and the all stainless replacements who I contacted. I believe his explanation of the problem. He stated this has only been an issue on Parkers and he hired a lab to determine what was happening. The results found the rubber gasket that Parker was/is using wasn't compatable with the ABS plastic and was "gassing" leading to degradation and cracking starting where the gasket meets the plastic cup/rod holder. These cracks were not visible from the top of mine but went almost all the way through. Light finger pressure in an attempt to inspect the cracks was all that was necessary to cause what was seen in photos. Gaskets are not supplied by the company as most people use a 4200 bedding instead. The owner told me he sold 20,000 of the plastic ones in the past 8 yrs. and has only seen this issue with Parkers that have used this rubber gasket. He also said he had notified Parker of the labs's results about the gasket and thought they were now using a different gasket. My boat was manufactured in Oct. 2017. I'm replacing all four of mine with the stainless version sold by Mate Series. They are heavy duty, highly polished 316 stainless and look very good on boat. Here's the stainless upgrade.