Thanks Linlor, yes I do have the 25th airboxes and you are absolutely right about those frames. I figure that there are at least 64 different known configurations of them. For that reason I sell the channel in four foot lengths and the felt in eight foot sticks. The channel I have is pressed, not bent on a break, and is within a fraction of a millimeter to OEM dimensions, but not absolute. I was more concerned with making a channel that perfectly fit the currently available modern style window felt.