Product review (4 stars): Your dryer uses one? Then keep a spare!
Always keep a spare around, sometimes they just open up for no reason and you won't get any heat. Sometimes your teenage kids will fail to clean the lint screen for several loads, causing it to overheat and trip. Since these don't reset, they have to be replaced. A 5 minute job on most dryers. (pop off the bottom cover and it is on the blower housing, use a stubby 1/4" nut driver) You tube has videos.