I'll have to go hunt them up again. The only difference between brand new keys and these dyed ones is a slight green tint to a couple of stems. The keycaps didn't take any dye at all. I'm pretty sure this is because we used an acid dye, which is designed to work on wool and other natural fibers. Dharma makes many different types of dyes, and I believe they have one that is designed for synthetic fibers which is probably ideal for dying PBT keycaps.