Oh.. the color on the inside top of the Swiftech GTX is going to fade and there'll be some black dye coming off. Not to worry. Its perfectly normal. No, the top of the Apogee GTX is not made of delrin, but those who are scared of any use of aluminum are foolish because the plating is of considerable quality. Don't even think of painting anything on the inside of the block. You will wreck the highest performing water block in the market.