Review on 🔥 Geekworm 12mm Aluminum Alloy Heatsink (C235) with 30mm Cooling Fan Support – Compatible with Raspberry Pi Compute Module 4 CM4 Motherboard by Terrance Duncan

Most likely just a casting, hardly machined. It's all powder coated so file/sand/buff the finish on the SOC riser for best results. The included thermal pad isn't too bad, although I replaced the SOC pad with a silver one after a while. Average SOC temp with thermal pad was 40°C (hovering around 60°C without heatsink), with Arctic Silver I didn't see SOC temps over 38°C under reasonable load. In general, an excellent product and small "cons" are fully justified by the low cost.