I bought these to see if the brand's diamond tipped drill bit set (Drilax) was any better than the less expensive similar 50 piece sets. In the box. They weren't. In fact, they're exactly the same as the cheaper 50's. Box sets, they're a lot worse anyway. My impression is that all of these 50 piece sets are from the same manufacturer but from different retailers charging different prices. I've tried 4 or 5 of these kits from different companies and they are all exactly the same, just the prices are different.