The springs seem to be OK so far, but the ones listed didn't make it. There were only two sets of 4 0.5 inch ID springs, which is contrary to what is stated in the description of this product and what is stated in the listing in the box. Since I have a 3/8" shank that they cover my options are more limited than I expected. I don't have machine tools to measure wire gauge, so I can't say anything else on this list is inaccurate (although it very likely is), but I can easily tell if there aren't 1/2" bore springs.