The cooling function should support safe, rapid cooling to set transfers and reduce ghosting, especially with sublimation. Look for an integrated fan or active cooling path, plus reliable temperature control that maintains consistency after cycles. When shopping among the listings, note models with solid metal or sturdy plastic construction and a robust heat-cool cycle, along with safety features like overheat protection and automatic shut-off. This deep dive helps you understand how cooling affects throughput and finished quality across projects like T-shirts, caps, mugs, and plates.