Been a little suspicous of the newer mantles for a while, having acquired a supply of the old radioactive happy mantles with the little metal clip, the difference is clear, modern on the left on the 46 vapalux, happy mantle on the right on the 58 tilley, would have used a 40 tilley in comparison but it was raining and the tube rubber leaked. It appears the radioactive coating makes a difference as well as the shape the mantle takes.
