I would think at low temperature dryouts, you would get a lot of use as nothing will melt, just evaporating the moisture out. I did put on in the toast oven/rod dryer at 250 range, took some time but they did turn dark blue again. Johnson deal on 14 oz for $10 is not too bad. I just have kept the last two HF ones and have about 3 left, so I will dump them and have enough I think at a much higher price (but got use of them prior).

Redbeard or someone mentioned the HF ones unscrew, confirmed.