I bought a terribly expensive bowling ball about 4 years ago, a Hammer Jigsaw Corner. It was a great ball, up until I didn't use it for about a year and it just sat in the bag in the hall closet, and the coverstock split all the way around. So there goes that money, up in smoke. Grabbed some of my carbide holesaws and drilled plugs out of the coverstock, and that's what fills the center of that stem cap. I jokingly refer to it as my "$200 gap cap." I'm drilling out more plugs to try to lessen the blow of losing the bowling ball. At least it lives on. It's already made another, right there in the sorta-middle of the group: