Review on 22-Piece Screw Extractor Set - Easily Remove Stripped Or Damaged Screws With HSS Broken Screw Remover Kit, Magnetic Bit Holder, And Socket Adapter From Nuovoware by Steve Campbell

Drill bits are either not hard enough or not sharp enough to drill into any bolt that's remotely hardened. Had a self threading bolt break off in old threads, tried starting drilling the initial hole with sizes 9-4 but never made more than a dimple with any. No instructions included with the kits. After getting a pilot hole started with a titanium drill bit I was finally able to seat an extractor, used my adjustable clutch drill and incrementally increased torque 1 click at a time, extractor bit broke on #15 out if 21 adjustments. Now the extractors are hard, lol! Now I've got a hardened piece of extractor stuck in the bolt that is stuck in the threads. FYI, the extractors are harder than my titanium and even cobalt drill bits. Now I'm looking for a machinist that can end mill hardened steel into the bolt and just rethread the hole.