Designed for extract chilling Richer flavours and aromas Durable Rapid cooling Easy to use The Nucleus Paragon Chilling Rock is a simple and effective way to enhance the flavors of your espresso. Developed in collaboration with Zurich University of Applied Science, the Paragon Chilling Rock quickly cools down the extracted coffee as it touches the rock, locking in more flavors that would otherwise have been lost without the chilling technique.