Dye Sub Pressing Mat / Heat Press Replacement Mat 15x15 is a great addition to any heat press machine. The Silicone Mat helps to evenly distribute heat and also covers exposed images when you are pressing transfers.
I was having trouble getting consistent pressure on my clamshell press and it was messing up my sublimation. This mat is perfect for that. It's thick, heavy, and helps with the heat. I would totally recommend this as an added layer when sublimating.