I had to remove the back of a Panasonic microwave to replace a fuse. I ordered these as two of the screws were TORX security screws. To my surprise, the hole in the bit was too small and the pin in the screw sheared off. It is now stuck in the bit, rendering the bit useless for the rest of the second torx screw. The hole had to be made larger in order not to cause this problem. Not sure if Panasonic microwave screws or bits are to blame. However, the beat was useless.