Well, after breaking every Torx wrench I have, stripping every Torx screw driver in my shop, running to home depot to buy T-15 driver bits, (breaking both within 10 minutes) ordering a proto impact T-15 driver bit and breaking it immediately after waiting a week for it to come in I'm at my wits end......here's the problem. Leupold Mk-4 tatical aluminum rings with steel T-15 head screws that I mounted a couple years ago and now am trying to loosen....I dont remember over tightening them as I only used the cheap L- wrench that came with the rings when I mounted it. I'm thinking that it has something to do with the aluminum rings and steel screws, I'm wondering if some sort of penetrating oil may help but these things are stuck tight!! I have had similar problem with some other aluminum rings I have had and wound up cutting them off with a Dremel tool.....I really don't want to do this again. But I'm fast approaching the cost of the rings just in driver bits Anyone have any ideas? I'm almost wiling to ship them and the Mk-4 scope they are holding to anyone who wants a scope that's not quite mounted level.... Has anyone else ever experienced this problem?