Product review (1 stars): NOT heat resistant
Thought the magnet would be great.  They are generic magnets (not neodymium).  I didn't think about the plastic needing to be heat resistant (DUH!) for my gas range.  The plastic seems to be polystyrene.  They melted/warped the first time I used a large skillet and high(er) power.  I ended up buying silicone type gap fillers - they work fine (and are much cheaper).