Still working on kitchen remodel. Yesterday was installing mop boards on island. They need to be removable so I can get at electrical for oven and stovetop. Using SS trim screws, they have a head about the size of a larger finish nail. t-10 torx head, pretty small. Drilled a pilot hole, mop boards are red birch. First screw, snapped the bit
. Remembered I had this set of my dads, used # 7 bit, worked great, countersink is adjustable. Set has been around since I was a kid.