What it is Blood Core is a slow-reveal Macaron made from teacore leather. It starts out black and, with use, the color underneath gradually shows through. Why it’s different This one’s a long game. Think pet turtle, not puppy. All my fidgets are built to last for years, but Blood Core may take longer to “wake up” than you expect. How the color works Teacore leather is dyed one color, then overdyed black. Blood Core: red underneath, black on top Alien Blood Core: green underneath, black on top Want the reveal faster? Yes, you can sand it to get to the color sooner. Also yes, that voids your warranty. (The lawyers insist I ruin everyone’s fun.) Specs Diameter: 1 1/2 inches Height: 1 inch (1/2 inch for each of 2 fidgets) Weight: 1 ounce Leather note Core leather is from the Rose Anvil x Seidel Tannery collaboration. It is not a pure vegetable-tanned leather like most of my lineup. It’s a combination-tanned latigo: it starts as a chrome tan for durability and flexibility, then gets a heavy vegetable retan to add body and better patina over time.