1995 Chevy Blazer Silver Warranty Button

I purchased a used engine as a replacement engine for my Blazer. There is a silver button glued onto the engine. It says warranty void if removed. The only other time I saw a silver button like this was when I used a remanufactured engine on a customers truck where I work at. I am a diesel technician by trade. Is that silver warranty button a signification of a remanufactured product or simply what does it mean?