Avoid eBay mystery boards. Stick to known reliable sources:
It sounds like you’re asking about the — a popular DIY pulse induction metal detector project, often sold as a PCB + components kit. surf pi 1.2 kit
Strictly Through-Hole (DIP) components; no surface-mount (SMD) parts, making it accessible for beginners. Typically includes adjustments for Power Supply: Avoid eBay mystery boards