The button has been roughly repaired, and this rework opens doubts if the whole product is a brand new item, or no. Apart this cosmetic issue, the real problem is that no technical label exists, either on drill and battery. The ce mark on the label rises doubts about it. The operation manual it's a big joke and again there's no reference about the model, and technical specs are missing. No way to know what buttons do, other than guessing or relying on own experience with similar products.
All in all, it could be a brand new one, or a rework of a detective device, there are doubts about safety, and how to use it properly. Is it a good bargain, or will it be a waste of money?