1. It is not necessarily a semi-finished product, because some of the trademarks on the light bulbs can be erased. I have tried this before. I rubbed the light bulbs in my hands and waited a moment to see that the trademarks were gone.

2. Take your bulbs that don’t light up and try them in other lamp holders to determine whether your current lamp holders are in poor contact. Then throw away the ones that don’t light up and confirm that they are broken. If you want to collect it, you can put a label on it and indicate it.