They're significantly larger the standard sinks that come with most manufacturer's video cards and are 100% CNC machined copper coated with nickel. To my surprise, each sink comes with a perfectly sized piece of thermal adhesive on the backside. All you do is peel the clear plastic film (see far left) and stick it on. As I found out with my Radeon 8500, the adhesive isn't permanent but it works quite well (you can shift it slightly with your fingers if you really try) and is ready to go seconds after application, as opposed to epoxy which takes time to harden. Now you may think I'm crazy for recommending thermal tape instead of epoxy and perhaps you're right. However, the difference isn't going to be anything special and definitely not something I'd be able to detect with a normal person's equipment.